The lake’s origins are tectonic. During the Quaternary Period millions of years ago, strata subsided, forming a tectonic trough that was covered with glacial water and precipitation.

Initially, the water level was 60 to 100 meters higher than it is today. It has been given different names, such as Lake Ballivian, Michin, Tauca, and ultimately Titikaka (Leveau et al, 1984).

From a latitude of 14ºS, the Andean mountain range splits into the western and eastern mountain ranges, forming a very extensive, flat, and high region between 3,700 and 4,500 meters above sea level, giving rise to the Northern, Central, and Southern High Plains, which occupy part of the territories of Argentina, Bolivia, and Peru.

Lake Titikaka is found in the Northern High Plains, Lake Poopo is in the Central High Plains, and the arid salt-mining regions of Uyuni and Coipasa are in the Southern High Plains. Lake Titikaka is found within a closed basin with an area of 58,500 km , of which 8,500 km is the lake.

Lake Titikaka is the highest navigable lake in the world. It is the 21 st largest lake in the world, and the second largest lake in South America, after lake Maracaibo. The lake is divided into two lake basins: The Greater Lake, or Chucuito, and the Smaller Lake, or Huiñaymarca. These are connected by the Tiquina Strait, which is 850 meters wide and 21 meters deep.

The system as a whole is closed (endoreic). Rain is the only incoming source of water and heavy evaporation is the phenomenon that maintains an almost constant water level.

Bay of Puno

The only outlet for water is found at the extreme southern end of the lake, giving rise to the Desaguadero River. The riverbed is 3,804 meters above sea level, and the water empties into Lake Poopo, which is in Bolivia at 3,686 meters above sea level.

The RAMSAR Convention has declared Lake Titikaka to be a RAMSAR site, for being a resource that serves as a biodiversity habitat that is very important in the biological chain of many species, and especially birds.