Napahai Natural Lake Reserve is 3,270m above sea level and covers 660 square kilometers. It is about 8km northwest of Shangri-La town in Yunnan Province. It is both an ideal field for herdsmen and a paradise for many species of birds. This is, in the true sense, a seasonal lake. When summer comes, snow on the adjacent mountains melts and flows down into about ten rivers forming a vast lake. In the dry season, Napahai becomes a boundless green grassland - the best time for herding sheep cattle. Every Steptember the lake again turns into a temporary habitat for migratory birds, such as bar-headed geese, wild ducks and black-necked cranes which is one of the 12 rarest bird species in the world. During this period, the lake becomes an ideal place for ornithologists from around the world.