The park's namesake canyon, Ob Khan, features limestone walls that reach heights of up to 30 meters above the river level.
The area was originally designated as a forest reserve before being officially declared a national park to protect its specific watershed ecosystem.
The geological composition of the gorge provides evidence of centuries of erosion from the Khan River cutting through limestone bedrock.
The park serves as a critical habitat corridor connecting fragmented forest patches in the Chiang Mai province.
Archaeological surveys in the region have occasionally unearthed prehistoric tools in the surrounding foothills.
Ob Khan National Park is defined by its deep limestone canyon carved by the Khan River, creating sheer cliff walls and natural swimming holes. The park spans approximately 484 square kilometers, covering mountainous terrain in the Hang Dong, Mae Wang, and Samoeng districts of Chiang Mai. Visitors can explore a network of nature trails that traverse deciduous dipterocarp and mixed evergreen forests. The park features the Ob Khan Gorge, a narrow section of the river channel characterized by high, rugged rock formations. Several waterfalls, including Tat Won and Mae Sapok, are located within the park boundaries. The park serves as a watershed area for the Mae Wang River basin. Diverse wildlife, including barking deer and various bird species, inhabit the dense forest canopy. Picnic areas are located near the riverside, providing access to the water for wading and recreational swimming.
The viewing platform overlooking the narrowest point of the Ob Khan canyon.
Bring sturdy, water-resistant footwear as rocks near the riverbed can be slippery.
Pack insect repellent as the dense vegetation near the river attracts mosquitoes.
Visit on a weekday to avoid crowds from Chiang Mai city, which is significantly busier on weekends.
Do not attempt to swim in the canyon during the peak of the rainy season, as flash flooding can occur rapidly.
Some remote trails may be closed during the peak rainy season for safety; check current conditions at the park entrance.
Maintain silence near wildlife habitats; carry out all trash to keep the river area pristine.
