Chumpon is a town in south of Thailand which is the transit point for going to or returning from the island of Koh Tao.
My suggestion
There are lots of little roads in the north and south of Chumphon which are perfect for bike rides, especially around Pathio (not far from Chumphon airport).
The Khong Chiam region is still largely unaffected by tourism and, for those willing to explore it, offers spectacular scenery and the promise of peaceful days spent well away from the noise and chaos of the urban environment. With its waterfalls, cliffs and rock paintings, Pha Taem is the kind of place you simply never tire of exploring.
Elephant rides have become a major concern in many locations, but are still offered by a handful of so-called "sanctuaries" with the proposition to get close to the exotic and majestic animal. Elephant rides are offered on every street corner and Westerners have little knowledge about the cruel methods to succeed in training these enormous animals.
To set the scene for you, imagine 2,188 km² covered by 80% forest and populated with more than 800 animal species roaming completely free. Add streams, waterfalls and a mountain range amongst 2,000 plant species. Classify it all as a UNESCO world heritage site and you have the Khao Yai national park.