Koh Chang is a great playground for the trail and ultra-trail runners.

You can run on the beach, White Sand Beach or Klong Prao beach are the longest. You can also run on the roads which have beautiful hills but you have to be extremely careful especially during the high season, cars, vans, trucks and motorbikes are very dangerous, there are already lots of roads accidents, don't take any unnecessary risks.
Prefer the east coast to the west, it's quieter, the traffic is far lighter and then safer.

But for trail running in the jungle, it's better to contact an experimented guide who can advise you. Raht from Kohchang Trekking, or Thomas from Thomas Koch Travel & Adventure know the jungle very well and they can recommend different tracks and then you will have fun.

On the beach, asphalt or in the jungle, don't over-estimate your capacities and in any case, take enough water with you. The weather can be very hot and in the jungle, there is no wind and the humidity level is very high, you can dehydrate very fast. Don't go alone and all the time take a fully charged phone with you. You can get lost very easily and if something happens there will be nobody to help you.

EDIT 01 February 2019:

In August 2018 Teelakow announced that the UTKC will not be re-edited in 2019, they didn't get the permissions needed to organise this fantastic race. It was a big disappointment for thousands of runners.

But don't worry, the UTKC 2021 is back!
Registrations will start on the 9th of September 2019 and the race days will be on the 15th and 16th of February 2020.
There will be 4 races, 14 km (376 m D+), 34 km (1,258 m D+), 70 km (2,844 m D+) and 100 km (4,180 D+). You will find all the contact information at the bottom of this page.

Being a runner and a trail runner, I recommend the Ultra-Trail Unseen Koh Chang which is held every year, normally in February, on the south-east of Koh Chang.
I have already done it a few times and even if you're not a professional runner, this is an interesting competition and a very good experience. I used the word 'competition' because the UTKC belongs to the Asia Trail Master and it's one of the toughest and most technical ultra-trails.
Every year it attracts around 2000 runners from about 30 different countries. There are lots of professional runners but also lots of amateurs who just come to have fun and this is what I like about this trail. People are supporting and helping each other. It's more like having a long trek with friends than doing a competition.

The date is normally released around July-August but don't worry, if you follow my News page or Facebook page, I will announce it as I will do it myself.

The UTKC is divided into 4 different trails: 13, 35, 70 and 100 kilometres.
The registration cost includes your BIB with a chip for the time tracking (which must be picked up the day before the start), a race sport shirt, few give-away from their sponsors and if you pass the finish line you will get a medal, a finisher t-shirt and for the 3 bests of their category, a cup.

When you register, the insurance is also included in case of an accident, several water stations with water, energy drinks, fresh fruits, food, cold sprays, medics, photographers everywhere on the tracks (for your memories) and after the races, free Thai food, more fresh fruits and cold drinks (water and energy). All tracks are clearly marked that you don't get lost. A GPS tracker is supplied to the 100 km runners.

The races start at Salak Phet school on the south-east of the island. Normally the 100 km is the first to start on Day 1. The 70 km will start a few hours later. Then on Day 2, early in the morning will start the 13 and 35 km just before sunrise.

If you normally run once a week, the 13k will be fun, even if those 2 big hills will almost kill you :) But it's part of the game. The track is using the old asphalt road, a small part in the jungle, then Wai Chaek beach and you will end on asphalt. For a normal runner, it will take about 2 hours. I have done it, it was nice. Like it's the easiest, it also attracts lots of amateurs.
Even if it's short and early in the morning it will be hot, especially for the last kilometres with the sun burning your face without a blow of wind. Carry with you a small bottle of water in a belt, in your hand or in a bag that you can also refill at the water stations, you will enjoy it.

(Pictures I took of the famous hills. They are steeper than they look like)

The 35 km is tougher. I have also done it and count between 5 and 8 hours to make it if you succeed to make it. So you got it, it's a long run even if you will spend a lot of time walking. The most difficult is the heat, combined with the steep hills, you will sweat like crazy and your body will suffer. Pain will become your best friend.
There are water stations every 5 kilometres with fresh fruits, drinks and cold sprays. Take your time to hydrate your body, drink and eat well. For this race, I really recommend a hydration bag or vest with at least 2 litres of water. On the last one I did I had a 2 litres bladder in my bag and 2 times 600ml soft flasks on the front pockets that I was refilling at each station. Believe me or not, during the whole race I drank almost 7 litres but I wasn't dehydrated and didn't get any cramps. I also had a few energy gels and cereals bars, sweet and salty to get more minerals. Because of the heat, you won't feel thirsty or hungry, just push yourself to eat and drink regularly, it's not a question of training, shape and mind, it's also a question of nutrition.
You don't need to be an over-trained athlete for this one but you need to have your body and mentally prepared before. There will be lots of uphills but also downhill walk which means lots of muscle pains.
Even completely exhausted you will get the last power to pass the finish line and you will be proud of yourself!

The 70 and 100 km are the most difficult and you really need to have good preparation and to have done a few other similar trails to be able to do them. They both include the night in the jungle and you have to know that you won't be alone, the jungle is also the residence of pythons, king cobras, vipers, tarantulas and other animals and insects I wouldn't like to meet. But don't worry, you have more chance to finish on the podium than seeing one of those creatures.

For the 70 and 100 km races, there is mandatory equipment you need to carry with you. There is also a briefing a couple of hours before the start.

During the Ultra-Trail Unseen Koh Chang, you will meet lots of people, see very nice landscapes, maybe get a new experience and if you pass the finish line, you can be proud of yourself!

So why not combine your holidays and your hobby or sport and plan your trip during the UTKC? If you decide to spend a night or more on Koh Chang before or after the trial, book early enough. There isn't so many resorts and guesthouses on the east coast and during the event, they are normally fully booked.
If you stay on the west coast it will take between 30 minutes and 1 hour to reach Salak Phet depending on where you stay. If you need any help to organise your trip, your stay or your trail, you can always send me an email or a private message on Facebook and I will help you with pleasure.

For more information about the UTKC you can also contact Teelakow (organisation):

- Facebook page: www.facebook.com/teelashot/
- Website: www.teelakow.com
- Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

Ultra-Trail Unseen Koh Chang:

- Facebook page: www.facebook.com/ultratrailunseenkohchang/
- Website and email: same as Teelakow

Pictures credit: Teelakow / The Memory Shot