Wheat fields in Lake Yamdrok. This lake is the largest in China, and one of the three largest sacred lakes in Tibet. It has an area of 638 km ² and over 72 km long. The lake is surrounded by many snow-capped mountains and is fed by many streams, but only has an outfall at the western end. According to local mythology, Lake Yamdok Yumtso is the transformation of a goddess.