Thac Ba Lake is one of Vietnam’s three largest artificial lakes located both in Luc Yen and Yen Binh districts, Yen Bai Province. The lake is not only a beautiful ecotourism site but also a national vestige.

This artificial lake has an area of 23,400ha and 1,331 islands and hills with diverse ecological environments. It is also famous for the first hydropower plant of Vietnam. The water in the lake is blue and clear, and imprinted with the reflections of the surrounding ancient forest. The thousands of hills and islands feature caves such as the Hum, Cau Cuoi and Bach Xa. The Thac Ba Temple always draws visitors.

Floating on Thac Ba lake, we could enjoy the pure air with the sparkling water on the grandiose mountains and islands. Not only being a landscape, the lake also joins in the process of protecting and improving the environment. Visitors would visit the old forest, green hills and the limestone mountains on the water. The tour of Thac Ba has been attracting many people with the destinations like limestone caves on the lake. Thuy Tien cave is located inside the mountain with the length of 100m and the stalactites of nine mermaids. Xuan Long cave is located in the limestone mountain. The stalactites would surprise the visitors with free and relaxed feeling.

Thac Ba reservoir covers a total area of 23.400 ha, of which 19.05 ha is water area and the remaining 4.35ha of islets on the Reservoir. The length of the Reservoir is 80km, maximum width is 10km, the average depth is 15 - 25m and maximum depth is 42m.

Thac Ba Lake is not only a beautiful landscape, but it is also a national vestige. In 1285, the Thu Vat Battle took place under the command of Tran Nhat Duat against Mongolian invaders. During the resistance war against the American, Thuy Tien cave is the revolutionary base of Yen Bai provincial committee.

Thac Ba is recognized a place of historical and cultural interest by the government. There are major plans to develop eco-tourism resorts in the surrounding area. For a long time Thac Ba Lake has become Yen Bai people's pride.