The actual 1st edition of the MSIG Thailand Action Asia 50 will be December 17 2017, but there is an opportunity to part of only 100 runners in the zero edition free of charge entry Sunday Jun 4 2017 (10km / 20km / 50km) on a first come first serve basis after making a donation of USD 10 that 100% will go towards the Doi Inthanon tree planting. Longer term the villagers need water dams and trees planting so this is a fund raising charity exercise to help Doi Inthanon.
Location 1 hour 20 minutes from Chiang Mai with international flight arrival at Chiang Mai recommended or many connecting flights from Bangkok.
Note in Dec the temperature is cool, but in June it will be baking hot so make sure you are use to the heat as was 39c in May during some test runs at lower elevations.