Bhumibol Dam (Yanhi Dam)

Bhumibol Dam is Thailand’s tallest dam at 154 metres, a concrete arch structure spanning the Ping River in Sam Ngao district, Tak. Completed and opened by King Bhumibol Adulyadej on 17 May 1964, it was Thailand’s first multipurpose dam project and remains the country’s only concrete arch dam. Entry to the dam grounds is free, open daily 08:00-17:00.

Construction began in 1958 under the name Yanhi Dam; King Bhumibol granted royal permission to rename it after himself in 1957, and both names are still in use — EGAT, which operates the site, calls it Bhumibol Dam officially, but “Yanhi” persists locally. The reservoir behind the dam holds up to 13,462 million cubic metres of water, backing up the Ping River for tens of kilometres north toward Doi Tao in Chiang Mai province.

Most visitors come for the reservoir rather than the dam wall itself. Boats for hire from the dam’s pier — roughly 30 minutes each way — reach Phra Phutthabat Doi Khao Nam, a hilltop temple on a mid-reservoir island holding a Buddha footprint shrine and a glass-footprint pavilion, with open views across the water to the surrounding hills. A second island, known locally as Valentine Island, has a sand beach where swimming is possible. Longer boat and raft trips, some towed by tugboat, run further up the reservoir past Doi Chao Pho Luang and Tham Aap Nang toward Doi Tao, for travellers who want to cover more of the lake in one outing.

Insider Tip: Book a boat early in the day — mornings on the reservoir are calmer and cooler, and the light is better for the views from Phra Phutthabat Doi Khao Nam before afternoon haze sets in over the hills.

The dam sits inside EGAT’s own recreation area, which also includes the Bhumibol Dam Golf Course, so facilities are more organised than at a typical natural attraction: EGAT-run guesthouses are available for overnight stays, and the grounds include gardens and viewpoints looking out over the dam wall and reservoir. Clear nights away from the dam’s lighting make this a reasonable stargazing spot, and fireflies are visible along parts of the reservoir shoreline in season.

Watch out: Boat hire isn’t included in the free entry — you pay separately at the pier, and prices aren’t fixed or posted, so agree the fare, including the return trip, before you set off.

Getting here means your own transport; the dam is well outside any public transport network in Sam Ngao district. For dam details or to arrange a guesthouse stay, EGAT’s site office takes calls on 0 5588 1237.