Seven Rila Lakes is a group of seven glacial lakes located in the Rila Mountains in Bulgaria between 2100 and 2500 meters altitude. They are small depressions connected by streams, forming cascades and waterfalls. Each lake has a name describing its distinguishing characteristic - the highest lake is named for its extremely clear water, while the deepest is Eye Lake which reaches 37.5 meters deep. The group includes Kidney Lake with steep banks, twin lakes, and Trefoil Lake with an irregular shape, as well as shallow Fish Lake and the lowest collecting lake.