Phu Sang National Park

Phu Sang National Park is a protected forest area straddling Phu Sang District in Phayao Province and Thoeng District in Chiang Rai Province, along the Thailand-Laos border. Established in 2000 as Thailand's 98th national park, it covers about 284 square kilometers of mountainous mixed deciduous and evergreen forest. It is best known for Phu Sang Waterfall, a rare warm waterfall fed by a geothermal spring, along with viewpoints, caves and nature trails.

Visitors can expect a forested mountain park with a rare warm-water waterfall (Phu Sang Waterfall) where water temperature is around 33-35°C, allowing wading at the base. The park offers short nature trails, viewpoints such as Doi Pha Dam overlooking the Laos border, limestone caves like Tham Pha Daeng, and mixed deciduous and pine forest. Facilities are basic and focused on nature sightseeing, photography and short hikes. The area is quiet and less crowded than larger northern parks.

Established on 8 June 2000 as Thailand's 98th national park, covering approximately 284.88 sq km. The area was previously part of protected forest reserves along the Thai-Laos border and was designated to conserve watershed forests, geothermal features and border mountain ecosystems.

Located in a border region inhabited by Tai Lue and other northern Thai communities; the park area is valued locally for its natural hot spring and waterfall, which are part of regional folklore and traditional use, and for its role in watershed protection for surrounding agricultural communities.