Created by a major earthquake in 1912, this deep, cerulean lake is fed by a glacial river and is notable for its forest of drowned spruces, the branches below the water so beautifully preserved by the cold water that local enthusiasts sometimes go diving here. There's a nice little beach for bathing, and a short trail through spruce forest to the end of the lake. You need a 4WD to drive here, 10km south of the village of Saty.
Technically, Kaiyndy is part of the Kolsai Lakes National Park, but you have to pay the entrance fee here separately, and its location is in a completely separate valley.