Latest Entries »

WTOC 2017

World Trail Orienteering Championships 2017 was held last week in Birštonas, Lithuania. I was selected to be a member of the Hong Kong team in both PreO and TempO competitions, and this was the first international sports (as opposed to academic) competition that I participated in.

The official maps are published online and can be found from the following link:


The competition programme began on 10th July with the model event in Birštonas. I familiarised the working of the TempO stations, including “loose or bounded, point or speak”, then competed in the qualification on 11th July in Harmony Park in the green group. However, as with all Hong Kong team members, I got poor result in the qualifications and didn’t get into the final. I didn’t realise that what I did previously was actually breaking the rules – I put the answered maps face-up on the table instead of face-down, and caught in station 2 leading to being marked X in questions 2 and 5. My end result was 575.5 seconds over 25 questions, placed 33 out of 40 in the green group.


Day 1

PreO model event held on 12th July and the day 1 competition held on 13th July. There were 21 questions in total with 2 questions voided, however, I only got 13 correct, placing me at 60 out of 66.

I answered questions 2, 5, 11, 12, 15 and 20 wrongly, which thorough analyses are below:

I found no idea even walking forward and back, drawing sighting lines and contouring from the cliff at the west, and guessed B. The solution was A.

My first instinct for question 5 was Z, suspecting that the flags were too low. However, I couldn’t verify the fact by whatever means, including compass bearing from various locations and contouring from 6, and finally chose B, but Z was the solution.

Although I suspected that B might be at the exact middle between the buildings, I couldn’t verify it and tried to draw multiple sighting lines. When I saw the marked line I chose A as the answer, but the solution was actually B.

It was out of my ability to note that B was off by a spur, and I wrongly chose B.

Although I suspected that the flags for 15 may be too far away, I couldn’t verify if it was true, and chose a letter for it. Someone reported that it was possible to confirm at the DP of 12 but I was not aware of that.

When I walked from south to north, I was flag A immediately and thought it was at the wrong place, and thought a flag B was hidden. When I walked to the point where I should be able to see the circled location, the flag did not appear at once, but when I walked further north a flag B appeared. Although I had thought about the possibly of Z I was too careless to answer B when I saw B appeared at the next forest corner, probably due to time constraint.

Question 13 was voided because the control description said A-B but there were 3 flags in the terrain. The 3 flags A-C also appeared on the solution map with the control description saying A-B, a very stupid mistake of the organizer.

Question 18 was voided after a protest where the jury found the map and the terrain were unclear and confusing.

Day 2

Day 2 competition was held on 15th July in Aukštadvaris. There were 28 questions and the time limit was 155 minutes. I attempted to solve the questions by instinct, which worked in the first half of the competition, where I got only 7 and 12 wrong in 1 to 14. However, the second half was total disaster, because the limit was too tight, I couldn’t even run along the trail to inspect some points far away, or had to answer something even when my instinct could not provide me a possible answer with no time to spare measuring angles.

For example, consider point 23 in the following map:

I tried to look at it from the north, but I couldn’t verify the shape of the hill there. After I reached the DP from the south-west, I had already no time left to return to the north to verify it again, and chose a wrong answer.

Furthermore, my instinct failed to provide possible answers for most of the questions in the latter half, except the most obvious ones like 21 where all the flags were clearly off from the correct feature:

Finally, I only got 16 correct out of 28, and placed 60 out of 64, giving total combined result of 29 questions correct over 2 days, placed 59 out of 66.


The relay was held on 14th July at The Capitals Golf Club, Pipiriškės. 20 teams of 3 participated in the open class. There were 27 questions in the field, each team member had to answer 9 of them, however, controls 11 and 18 were voided after protest and control 27 was voided because there was a missing SI unit. Our team’s total corrected time was 14’38” with place 17, while 2 teams were disqualified because they used a pen in the competition.


I didn’t do well in this world championships, mainly because I was not used to international-level sports competitions. Actually this was my first time I participated in world-level sports competitions. The silliest thing I did was the rule violation in TempO leading to huge amount of penalty in the results. Also, the tight time limit of PreO day 2 also affected me as I had never run tight in time in previous PreO competitions I participated.

I am currently not interested to join next year’s event because it will be held in Latvia, also a Baltic state. Maybe I will wait until 2019, and participate in more events in Asia these 2 years. Also, there will be world ranking events in TrailO starting next year, just like the other three orienteering disciplines.


Last Wednesday was the World Orienteering Day (WOD), club over the world organised many orienteering events during the day. In Hong Kong, it was unfortunate that it rained extremely heavy to the extent that black rainstorm warning was hoisted by the observatory, resulting in suspension of work and school. The orienteering events were no exception. Despite the heavy rain, I participated in 3 WOD events in the evening after the rain stopped.

The WOD event by MetOC in Kowloon Park, originally scheduled to start at 11:00, postponed to 16:30 (actually about 17:00 because the organiser needed more time to set up the controls).

I took light rail and metro to Tsim Sha Tsui. During the 30-minute metro journey, I opened the online photo-O game by HKOC and completed 25 multiple choice questions, asking which flag in the photo was the one circled in the map. The result was published the next day and I got all correct.

The event by MetOC was free of charge and we could choose between an easy (standard) course and a difficult (window + corridor) course. I ran the difficult course and left immediately because time was running short for the next event due to the delay. As I would like to take first-hand videos in orienteering races in the future, I played with my video camera before and took a test video during this event, and the result was satisfactory so I could take a production video in the next event.

I immediately went back to the scout centre and entered Austin Station. During my way to Austin metro station, there were many property agents promoting “Ocean Pride” (海之戀), a new development in Tsuen Wan. I took the metro for 2 stations to Hung Hom, got on a cross-harbour bus, pressed the bell immediately when the bus started, and got off at the next stop. The event centre for the next event was just next to the stop where I got off the bus.

This event was HKOC Sprint Series (stage 3), a standard cross-country sprint orienteering race. One of the scouts in the troop I lead, Tavon Yum, also joined.

As usual, I used my GPS logger to get a trace. This time I also used my video camera to took a video, which John Wangki Yuen already had been doing for multiple times. I additionally used QuickRoute and RGmapVideo to generate an annotated orienteering video.

My performance in the race was not very good, with many small mistakes scattered along it.

I didn’t read point 4 carefully and went to the south of the flowerbed where the point was located on the north.

When I approached point 9, I didn’t make the required left turn and ran straight to the stairs.

From 10 to 11, I didn’t notice there was a passage south of 10 and took a sub-optimal route, going down the slope and U-turned to the point.

I also turned into the wrong path when approaching 12, and ran a wrong route leaving 12.

After leaving 17, I ran to the wrong direction.

I finished the race in 16 minutes and 44 seconds, even slower than John who made a large mistake running out of the map. Maybe I didn’t have enough map reading during the race resulting in running sub-optimal paths.

The 3rd sprint orienteering ranking event was held in Fung Shue Wo last Sunday. The venue was fun, including both park and village terrain in the same competition, with legs of different lengths mixed together demanding high level of concentration in the race.

I ran the M21 course, with my target at 800 marks hoping to return to élite class next year. I performed well in the initial half, with only little mistake made, but my performance turned bad in the final part of the race, which made me not achieved my target. As usual, I have recorded my GPS trace for analysis.

There was no route choice and little skill involved in the first 2 legs, serving as an introduction to the terrain. From 2 to 3, it seems that crossing the northern bridge is the only viable option, so I took it and ran along the edge of the lake (marked in magenta), not realising that a shortcut (marked in blue) could be taken.

There are two route choices from 3 to 4, the orange and the blue routes:

I took the blue route simply because there were less contour lines as I am extremely bad in running uphill.

Controls 5 and 6 simply guided the competitors to another part of the arena, which is a village. Although there was really no technique in these 2 legs, I didn’t have the confidence to run full-speed along the drainage, and slowed down once in the process.

Control 7 was simply about running directly to the target in the right direction.

Control 8 was also easy by just recognising the high fence.

Then I ran to 9, 10 and 11, but after these easy legs I overspeed, missed control 11 into halfway of leg 12, and abruptly stopped when I saw an inappropriate geometric shape. I had to U-turn to the control and U-turn again to continue. Afterwards, I slowed down and jogged carefully to point 13, and passed the trap carefully to point 14. (If you turned left too early after point 14, you would enter the path south of the river.)

My performance turned bad from here onward. I attempted to run along the drainage to point 15, just like what I did to point 6, but this time the runnability was extremely poor. Moreover, I didn’t realise that the line symbol ending at point 15 was a high fence, rather than a high cliff or wall, therefore I stopped somewhere in the leg for nearly a minute trying to locate myself, and proceeded extremely slowly. Despite that I slipped and hurt my leg.

However, this was not the end of my bad story. I planned to turn right immediately after point 15, follow the blue route, turn left just before reaching a fence to point 16. However, I ran to a fence outside a park and became lost immediately, and had to return to the original position to re-orient myself. I found out later that I didn’t exaggerate my right turn enough to the blue route, and ran the red line instead.

I even didn’t know which path I was following in the process to point 17, then it was the end of the race.

Within a month, I returned to my “home stadium” for orienteering the second time. This event is composed of two parts: a team event and an individual Pre-O event.

Team Challenge

The team challenge is done by teams of 3. I signed up with Paul and Raymond, but at the event Raymond had got his leg injured so we started with 2 only. The race composed of compulsory points and free points:

  • Compulsory points: Points which every team members must visit in order.
  • Free points: Points which must be visited by at least one team member in no particular order.

Therefore, at the start of the race, we had to decide who would visit the free points. The simplest way is to directly draw a line on the map and assign each member to a region on the map, and meet at the finish expecting each member will return at roughly the same time:
team challenge map

I took the eastern part and Paul took the western part, and I went in the following order:

Paul returned to the last control earlier than me, and we read aloud the controls to confirm we really did visit all, and crossed the finish. However, Paul didn’t realise that he hadn’t punched the finish correctly, and resulted in a few minutes lost over our finishing time.

Pre-O Event

We all signed up for the Pre-O event in addition to the team challenge.

As John has already written a blog post about this event about the fundamentals of trail-O problem solving, and his brilliant photographs already serve as a great introduction to trail orienteering, I only focus on how I performed in the competition here.

Control 1 was easy, the correct answer could be identified by the correct railing.

Control 2 was also easy, the correct answer could be identified by the thicket corner.

Control 3 was a bit difficult. It was difficult to judge the height around the DP, so I had to go to the upper trail to estimate the distance.

Control 4 could be identified by walking down the stairs.

After control 4 there was a timed station. I didn’t performed well because I tapped on the answer board before I reconfirmed ABCDE when I saw the circled flag, resulting in the wrong letter tapped (I tapped on the letter B while my eyes were looking at slight left before I realised that there were no flags on the far left).

Control 5 could be identified by walking near the control cluster. The only purpose of the decision point was to identify which flags were A and B.

I chose the flag to be correct at control 6 because I found nothing contradicting the map.

The flag for control 7 was correct because it was clearly at the middle of the walls.

Controls 8 and 9 were the most difficult. I tried walking to the top of the platform on the east, along the circular path, etc. and thought that one of 8 and 9 would be Z because by viewing from the top of the platform, 8 and 9 were on a straight line but A and C weren’t. I could not find anything contradicting flag C to be control 8 so I chose C to be the answer of 8. However, I identified the valley where flag A was on incorrectly and didn’t realise that the circled valley was invisible for control 9, and made the only mistake in the course (excluding time controls). Control 10 was easy because there was no flag on the circled feature.

Control 11 was also easy because I could walk near the shelters. (The shelters were in forbidden area but the ground outside the building corner on the East wasn’t).

Finally I made one mistake but there were competitors who got all correct. I was not satisfied with this result because, being an elite competitor in Hong Kong, I expected myself to got nearly all correct, and the mistake made me to become just about average in the field.

In my 5 years of orienteering life, I mostly participated in individual race in my own, with only very few team races, because finding teammates was very difficult. This race, “Festival of Sports Orienteering Relay”, is held every year, but I didn’t bother to join because I was not confident about my ability to finish the race. However, as my technique improved, I would like to join the race this year. I looked for teammates among my club, other scouting friends, and also my ACM-ICPC teammates, but everyone was busy travelling, doing expedition, camping, etc., in the Easter holiday, or had already got a team at the moment I contacted her.

Luckily, at the MetOC ranking event in Tai Po, a couple, Hanifa and Raymond, approached me looking for the third teammate for entering the MIX (men and women) class. As I would also like to find a girl to enter the MIX class, I immediately agreed and filled in the online application form, which was on the due day already. We agreed to have me run the first lap, Hanifa the second, and Raymond the last. This arrangement was critical to our success in the event, explained later on.

Relay orienteering is different from individual orienteering that the competing units are teams of 3 (teams of 4 with at least 2 women for sprint relay). In individual orienteering, because everyone in the same class is running the same course, interval start is used to minimise following. However, in team orienteering, the situation is different. The teams of 3 are competing head to head, where everyone in the field are running similar but different courses, but the combined course of every team are the same, which forms the basis of fair competition. Mass start is used, therefore the one crossing the finish line first is the winner, but because everyone is running a different course, he cannot blindly follow the others and must use judgement to decide.

Note the string ABCBA in the above course. It indicates the variant of my course, which means the course contains 5 forks starting/ending with common controls with 3 variants each (labelled A, B and C), and I run variants A, B, C, B and A for the 5 parts in order. The length of the parts and the variants are unknown to the competitors, except that over all 3 laps we run all variants A, B, C for each part.

The relay rule is that, when the competitor running the first lap passes the spectator point, the next competitor enters the start area and prepare for the relay. The first lap competitor, upon entering the finish, clap the hand of the second competitor to start him, completing the relay. However, if the first lap competitor cannot return to the finish before a specified time (in this race 90 minutes after the start), all the second lap competitors are mass started without completing the relay, which make them rank below all the relaying teams. The relay between the second and third laps are the same. Therefore, the major objective for the first and second lap competitors is to return to the finish before the next competitor is mass started. Because of that, the placement of competitors is part of the strategy, placing the fastest competitor first gains time for the remaining laps. If the first competitor goes wrong, resulting mass starting of the second competitor, no matter how he performs the team already loses the race. However, if the first competitor is super-fast but the second competitor goes wrong, as long as he returns before the third is mass started, the team still has a chance to win the race, which actually happened to our team in the event.

Because I am bad running in the woods, I did my course slowly in the event, but I still went wrong at a few places:

From 3 to 4, I aimed at a wrong rock having another control, but corrected immediately after checking the code, only minor mistake here, but after 4, I tried to go straight to 5, but I deviated from the correct direction, couldn’t find the path and the spur and got lost. Also I had to stop and check feature many times from 5 to 6.

From 9 to 10, the technique of following came to play. After crossing the stream on the west of 10, I saw a competitor in another class going up the wood to a cliff in the direction where control 10 was in, so I followed him hoping that the cliff he was going was the correct cliff, and the result was really correct. I read the map to control 11 when going up the hill, therefore I immediately walked down at full speed directly in the correct direction aiming the hilltop of control 11 and passed him, then he in turn followed me to my control 11. I checked the code was correct, punched it, and left the control, but when he saw the number he found that it was out of expectation (because his control was different, not directly at the hilltop), and immediately got lost. This clarify the importance of locating myself continuously even when following someone.

I mass started at 10:30, and had to return before 12:00 or else my next teammate would mass start. Despite the mistake I made, I returned to the finish at 11:32, nearly half an hour before the mass starting deadline of the 2nd lap. Hanifa ran 92 minutes for the 2nd lap, more than the 90 minutes time allocated for each lap before mass starting the next, but because I returned early in the 1st lap, she still returned on time to start Raymond normally, who ran 64 minutes for the last lap, resulting in a total of 3 hours and 38 minutes and got the 3rd place, where only 3 teams could finish the race normally by relaying all the laps. The placement was crucial to our winning because the 4th team, although the overall time was slightly faster than us by 16 seconds, the 1st teammate ran overtime for 100 minutes, therefore couldn’t make her way to the finish at the mass starting deadline for the 2nd lap, even the remaining two laps were completed in about 59 minutes they had to be ranked below us, effectively giving their prize to us.

I think it was plain luck that we got medals in this event, because that among the 15 teams that started, 10 teams got disqualified (most probably because of mis-punches), 1 team ran overtime, and 1 team mentioned above ran over the mass-starting deadline because of the ordering, resulting in only 3 teams completing the race normally. Actually we were very slow, only hoping to complete the race, but completing the race is enough for the prize.

The result is posted below, note that the total time for the 4th place is less than us at the 3rd place:

And here is my GPS trace:

HKOC Sprint Series this year started last Saturday. The first stage was held in Kowloon Park, which is my club’s “home stadium”.

This race is not a gazetted event, which means it is mainly a practice event in my own view. However, as I was too familiar with this field, although I did generally well, I still made some mistakes.

The first mistake I made was at point 2, where I ran too fast onto the field directly to the opposite site without looking carefully at the stairs in the presence of people practising kung-fu.

Then to point 11, I also ran too fast overestimating the distance between controls, and stopped when I saw something inappropriate.

The circle on the west of point 12 was blocked, so I had to avoid it when going 11-12 and 18-19.

In leg 21-22, I wrongly reduced my speed on an earlier junction when running down the slope, unnecessarily reducing the speed.

For leg 24-25, I might have taken a bad route choice by going upstairs after crossing the tunnel, unnecessarily reducing the speed where I could accelerate till the end of slope and keep the momentum under the canopy.

Although all the above are minor mistakes, in sprint “every second counts”, and a few minor mistakes already accumulate to difference between the first and the middle of the field.

Overall I got the 4th place in class M21 among 11 starting competitors, which is in my expected range. More information can be found in the links below:

My trace:

Starting from this race, I will make an evaluation post for every orienteering race I participated, as part of my effort to improve my orienteering skills.

This race was very special, different from typical orienteering race by having the following:

  • The field was HUGE, combining Ngau Liu, Pak Shek Kiu, Fa Shan, and Shek Lung Kung, resulting in a map of A3 size at 1:10000 scale.
  • As the field was HUGE, in order to cater for courses of different difficulties, 3 starts and 3 event centres were set up, with baggage transfer to the main event centre done by the event organiser so that we could get out baggage after finish.

I participated in class MO, which corresponded to ranking class M21. However, I couldn’t finish the course within the 2.5 hours time limit hence couldn’t get any ranking score.

map with route

As I started my GPS logger too late, my route to point 1 was not recorded. I normally start my GPS logger in the 2-minute zone, however, I will do it much earlier in the future.

In leg 1, I originally wanted to follow the trail (marked in red in the below map) the whole length because my cross-country ability is crap. However, at the place where the trail is U-shaped, I couldn’t resist my temptation to take a short-cut across a short length of runnable forest (marked in blue), but I wasn’t careful enough and ended up in a wrong direction (marked in purple), which resulted in extra time instead of saved time.

Legs 2, 3 and 4 were basically stream-following, but because my cross-country ability is crap, and also I needed to verify my location multiple times along the route, my time was extremely slow, more than double of the fastest competitors.

On entry to point 5, after the water station, my plan was to enter the control point directly from the east (blue) but I couldn’t identify the entry into the woods, so I ended up following the trail (purple) and entering the control site from the south.

Legs 6 and 7 were easy legs that I made no mistake. However, when I went to control 8, I couldn’t identify the direction at high speed, forcing me to slow down around the region.

After crossing the marsh to control 9, I also searched for about a minute for the control point.

Disastrous mistakes came after control 9. From 9 to 10, I intended to use the marsh as an attack point, as shown in the map below. However, the plan failed as I didn’t realise I was already on the marsh (perhaps because it was dry), and ran all the way down (the purple line). Then I found the mistake because the surrounding was wrong, and had to return.

Leg 11 was good, and leg 12 was initially good, but I ruined it just before entering the control. Perhaps I had already used up all my physical fitness, after seeing a building, I misinterpreted the map and confused the large square (meaning tower for overhead wire) on the south and the small square (meaning ruined building) on the west, and ran into the tower thinking it is the small square inside the circle and tried to find a control point nearby where the reality is a dense forest, resulting in about 10 minutes lost.

I made no mistakes on legs 13 and 14, but committed a near-fatal one just after I left 14. I intended to follow the blue route on the map below to 15 (the orange route was excluded because it had excessive climb), but I entered the purple path by mistake and didn’t notice even I checked my compass multiple times. The compass bearing was slightly off but still within my tolerance, so I tried to use other features to confirm, but the undergrowth around was so tall so I couldn’t see any other things, and continued running off the wrong path. I realised I was wrong only after a long distance because the hill top near the orange path was too far away. This mistake costed me nearly 15 minutes.

After 16, I didn’t want to risk crossing medium green (marked in blue below) as the time limit is near, so I chose a runnable route even it was longer.

The fatal place was control 19. Although I had little difficulty finding point 19, I was literally TRAPPED afterwards. The blue route was to be followed, but the path to the west was hidden deeply so I ended up at the red point. I saw the stream, knowing I was at the wrong place, then I returned to the original place, tried to find the blue path again, and ended up at the red point again. I found the path at the third attempt, turned left and cross the stream, but the path disappeared once I cross the stream. I searched for a while in the forest, and found the path. However, after I walked a short distance (let’s call there place B), the path disappeared again. Then I tried to find a path to exit the area and couldn’t succeed. I was thinking that I crossed the stream out of the blue path so I walked around to find another place to cross the stream but ended up at the red place again. I followed the blue path again, more slowly to make sure that I would cross the stream at the correct place. However, I ended up again where the path disappeared in my earlier attempt (place B). I looked around more carefully and found that the path wasn’t disappearing, but just blocked by a rock and I could walk over it and continue. I then realised that I was at the orange spot and left the trap after 35 minutes since point 19.

As the time limit was already over, I walked back to the finish. This race is a disaster for me, I hope it never happens again.

More information can be found at the links below:

MTR Kwun Tong Line was extended with two new stations added this month, called “Ho Man Tin” and “Whampoa”. However, “Ho Man Tin” station is a complete misnomer: it is not located in Ho Man Tin at all, similar to “Lai Chi Kok” station which is located in Cheung Sha Wan.

Ho Man Tin Station is located at former Valley Road Estate, as the name suggests, near Valley Road. That particular place has its own name: Lo Lung Hang (老龍坑), which can be found in old maps. In contrast, Ho Man Tin is actually on the other side of the hill (Quarry Hill where Ho Man Tin Estate is located on, and No. 12 Hill where Oi Man Estate is located on), about 2 km away from the station. As the station is far from Ho Man Tin proper, it mainly serves the neighbourhood of Hung Hom, rather than Ho Man Tin. If you want to go to, for example, Kowloon Central Library or Pui Ching Middle School, which are located in Ho Man Tin, the best metro station is Mong Kok East Station, rather than “Ho Man Tin” Station.

Ho Man Tin Station is not in Ho Man Tin. There is still no metro station in Ho Man Tin, the nearest one is Mong Kok East Station, located not very far away from Ho Man Tin.

I have records of some journeys made by public transport for my analysis. The model I use is the generalised cost of the journey taken in isolation. In the value of time conversion, I currently use HKD 12.0 per hour as a passenger and HKD 18.0 per hour for walking, waiting or driving, using the price index of January 2015. These figures may be adjusted if I find them contrary to my personal preferences.

I consider, if the generalised cost is below 10, the journey is “cheap” that I am willing to travel on a frequent basis; if it is about 15, I am still willing to travel occasionally; however, if it is above 20, the journey is “expensive” and I tend to make arrangements to minimise the cost; if it is above 30, I start taking transport into consideration to decide if I am willing to go to that place to join the activity.

From my home in Mong Kok, a generalised cost of 10 can bring me to areas like Tsim Sha Tsui, Admiralty, Wong Tai Sin, while 15 can bring me to places like Kwun Tong, Causeway Bay, Lung Fu Shan (HKU). Travelling to suburbs like Tseung Kwan O, Fung Shue Wo, Fu Shin and Chai Wan Kok costs me about 15 to 20, while travelling to rural areas in Hong Kong SAR like Sai Kung, Sheung Shui, Stanley, Tin Shui Wai, Yuen Long, Clear Water Bay, etc., normally costs me 20 to 30, in some extreme cases, the cost may even reach 40 like going to Wong Shek Pier.

There were a few recorded journeys where the cost is more than 40, these were normally long journeys involving rural areas and/or crossing the border. In particular, the journeys between Tai Hing and Tangjiawan, which are about 41 km apart, were the most expensive, costing between 190 and 200, mainly because they involved super expensive coach / ferry, long time in taking the coach and long time in multiple transfers to / from the ferry. (In my experience, the costs tend to be much higher if the points of the journey is separated by the sea. In these cases, Tai Hing and Tangjiawan are separated by “the great sea” (大海), because in Hong Kong everyday usage, “across the great sea” (過大海) means travelling to Macau, therefore, “the great sea” refers to Pearl River Estuary.)

Although the generalised cost is a good indicator of my willingness to take the journey, the longer the distance, normally the higher the cost. My analysis on the data has shown me that, by dividing the generalised cost by the square root of the distance, the resulting figure is statically irrelevant to the distance, and can be used as an efficiency index from travelling from a place to another. This number currently ranges from 2.79 (the most efficient) to 31.18 (the most inefficient), where the inter-quartile range is 5.18 to 7.83. The small inter-quartile range means that in most cases the generalised cost of the journey can be predicted from its distance. For example, taking the MTR East Rail Line from Mong Kok to Wan Tau Tong is very efficient (using very low cost to travel a long distance), where the index is about 3.82, while taking bus no. 1 from Kowloon Tsai to Mong Kok is very inefficient, where the index is about 10.73. A journey of about the normal efficiency is taking the Tsuen Wan Line and Island Line from Mong Kok to HKU, where the index is about 6.20.

The notion of transport convenience can be derived from the above index. If the index is high (inefficient), there is the possibility of using an inferior method (for example, from Kowloon Tsai to Mong Kok, a much better option is taking the MTR from Lok Fu to Mong Kok). However, if there is no method where the index is low, I can say that the transport there is inconvenient (hard to get there efficiently), especially if there is no efficient method from a place to multiple places. For example, Sandy Bay is a place where the transport is inconvenient. In contrast, the transport is convenient (easy to get there efficiently) if there exists a method, or even multiple methods, where the index is low. For example, the transport to Tsim Sha Tsui is convenient because I can easily get there efficiently from multiple places.

The first competition of Hong Kong Orienteering Ranking League (Middle / Long) 2016, the third full year since I become an orienteer, was held today. The event took place at Tai Mo Shan (大帽山), the highest hill in Hong Kong. As it is usually foggy on the hill, it is also called 大霧山, which means “foggy hill” and sound the same as its true name except the tone in Cantonese.

This was also the first ranking competition after I completed the lessons of level 3 orienteering course, which requires me to finish two ranking competitions scoring at least 600 afterwards in order to graduate. As I had never got 600 marks before in middle / long ranking events, this seemed to be a big challenge to me.

The weather today on the hill was, as usual, foggy to the extent that the visibility was only about 10 metres. This was certainly a good news for me, as other competitors who are physically fitter than me might not be able to run as fast as they would in normal conditions without making mistakes, which would probably increase the winning time, hence, the scores of all other competitors. However, the amount of climb in today’s course was large, as my physical fitness and cross-country ability is not good, I could not travel fast on the terrain as well.

I could handle the difficulty of today’s course using techniques learnt from the level 3 course, and also from my club’s training, like attack points, contouring and distance estimation. However, I was not free from technical mistakes.

I started the race at 11:58. I immediately climbed back to the road from the start, and walked (the road is too steep for me to run) to the water station, where I could follow the remains of a fence to control 1. I returned to the track, and identified the rectangular cliff as the attack point to control 2. Then I ran the track until an intersection on the right, and entered control 3.

I returned to the track and continued in a easterly direction, until a knoll appeared on my left, where I chose that as the attack point to control 4. However, I went to the wrong rock at the north, and returned to the control from there. I then ran down the path until the intersection at the north-east of control 5, and entered the control.

I returned to the path and ran to the west. I should have run about 200 metres before I look for the spur on my left, however, I couldn’t resist my temptation to follow a large group of competitors, and left the path prematurely in the region of striped green, even I didn’t feel that I had already run for 200 metres. However, being aware of the fact that I was taking a chance, I returned to the path fast when I couldn’t match the features at the first glance, and ran to the correct one to control 6.

Controls 7 and 8 were easy. I just followed the path until the undergrowth around me disappeared, identified the depression and headed directly to the group of rocks of control 7, and then to control 8 without returning to the path.

The leg to control 9 was a long leg. I thought for about 5 minutes, whether I should use the path to the start, or to climb the spur directly to control 1 after crossing the river. However, in fact, it was difficult to climb the spur after crossing the river, so I ran along the path to start, climb onto the road like what I did to control 1, and into the forest to control 9. I then travelled down, using a large rock as the intermediate, to control 10.

The biggest mistake I made today was from 10 to 11. I ran down the road until the correct place, but I deviated from the right direction when I was slipping down the slope, resulting me in green region where I could not locate myself. I then only recognised the sound of water flowing down the river on the south, and blindly travelled to the north until I exited the dense forest, where I could find the knoll immediately. Afterwards, I contoured to control 12, ran downwards to the road, slipped on the spur to control 13, crossed the two rivers, went back to the road, punched the last control and finished the race in 99 minutes.

My calculated score today is 685, meeting my short term target of 600, and is the best in my middle-long ranking. However, a lot of my classmates in the level 3 course could not finish the competition. I hope that I can get my level 3 certificate after the HKOC sprint ranking, postponed due to unstable weather, next month. I also hope that I can get continuous improvement in the coming middle-long ranking events, by learning through today’s mistakes.