From The Art and Popular Culture Encyclopedia
Band-e Amir is a series of six deep blue lakes separated by natural dams made of travertine, a mineral deposit. The lakes are situated in the Hindu Kush Mountains of Central Afghanistan at approximately 3000 meters of elevation, west of the famous Buddhas of Bamiyan.
They were created by the carbon dioxide rich water oozing out of the faults and fractures to deposit calcium carbonate precipitate in the form of travertine walls that today store the water of these lakes. Band-e Amir is one of the few rare natural lakes in the world which are created by travertine systems. In 2009, Band-e Amir became Afghanistan's first national park.