Doi Inthanon (2,565m) is Thailand's highest peak and the road to its summit is one of the best day rides in the country. The highway winds through montane forest past waterfalls, twin pagodas, and highland Hmong and Karen villages. At the summit, temperature drops below 10°C while the lowlands bake at 35°C.
Clone it to your planner, customize dates and stops, then ride. All free.