Doi Inthanon is the highest mountain in Thailand, at 2,565 metres, and the road to its summit is a ride into another climate. The air cools by ten degrees or more as you climb, the forest changes from tropical to a dripping cloud forest of moss, orchids and tree ferns, and at the top the temperature can drop close to freezing on winter nights. Chom Thong, the town at the foot, is where most riders turn off the main road, and Chiang Mai lies roughly a hundred kilometres to the north-east.
The road up is a good one, narrow and steep, with plenty of bends and a surface of tarmac that is generally good, though it can be slippery with mist. Two royal pagodas stand on a ridge near the summit, built to honour the King and Queen on their sixtieth birthdays, with gardens full of flowers. At the very top, a short walk leads to a shrine where the ashes of the last prince of Chiang Mai are kept, and a sign marking the highest point in the country.
The park is known for its bird life, and bird watchers come from all over the world to see its rarities. The Wachirathan waterfall, beside the road, falls in a thick, noisy sheet, and in the cool air it throws up a mist that drifts across the tarmac. Hill tribe villages of Hmong and Karen on the lower slopes grow coffee and vegetables, and fruit stalls along the road sell strawberries and peaches in the cool season.
There is an entrance fee for the national park, and a checkpoint near the base. Fuel is not sold on the mountain, so fill up in Chom Thong. A few food stalls and a small restaurant serve the visitors, and the market near the pagodas sells hot drinks. The road is open all year, but in the rainy season, fog and rain reduce visibility, and in the cool season, from November to February, the mornings can be very cold. Bring a jacket and gloves.