This natural phenomenon is the most popular summer attraction for Bulgarians. The glacial lakes, located between 2,100 and 2,500 feet above sea level, are located on the northwestern Rila Mountain, itself a stunning highland region on the Balkan Peninsula. The names of the lakes come from their shapes and qualities. The highest, Tear Lake, for example, is known for its crystal-clear water. The seven lakes are connected through small streams.