Located about 90 kilometers west of Gongbo'gyamda County, the Basum Lake is an alpine lake at the middle and upper reaches of the Ba River, which is the largest tributary of the Nyang River. The lake surface is on average about 3,538 meters above sea level. The lake covers an area of 25.9 square kilometers. The deepest part is about 60 meters from the surface. The blue, limpid lake water and the verdant mountain around the lake combine into a charming scene that can be compared with those in Switzerland.

In summer and autumn, when flowers bloom and the air is filled with their fragrance, bees and butterflies are seen shuttling and fluttering among them. Bears, leopards, goats, musk deer, Tibetan snow roosters and other wild animals look for food and sport in the forest. An islet in the center of the lake is an enormous "sheep-back stone" left by glaciation eons ago. Following the direction of the glacier's movement, one can discern distinct traces. On the islet stands a monastery of the Yellow Sect, which was built in the 17th century.

Going upstream from the Basum Lake to the source of the mainstream and the tributaries, one can see large mountain glaciers. With abundant snow, the long tongues of the lakes often stretch into the lush and green forest, the white snow shining through green trees. The bank of the lake is dotted with small villas of unique shapes, making a beautiful and comfortable holiday village.
In 1997, the Basum Lake was listed by the World Tourist Organization as one of the world's best tourist spots.