The unique Mertzbacher Lake is located in the Central Tien Shan, between Sary-Jaz and Tengri-Tag mountain ranges, at the altitude of 3304 m. It is called "the disappearing lake", and this is its main feature.
Twice a year the lake almost completely drains into the river Inilchek and re-formed by glacier water. In fact, it has two pools the Upper Lake and the Lower Lake, which is 400 m lower. The Lower Lake is surrounded by the ice dam, which breaks in the period of melting and the water goes into the valley. The Upper Lake, on the contrary, is always full.
Of all the lakes in Kyrgyzstan, this phenomenon is inherent only in the Mertzbacher Lake.