ORIGIN.- Many hypotheses exist to explain the origin of lake Titicaca. In its formation process there were other lakes that made up the region, such as lake Mantaro (3950 metres above sea level), lake Cabana (3900masl), lake Ballivan (3860masl), lake Minchin (3825masl), lake Tanca and then finally lake Titicaca (3810 masl)

The geological formation processes formed the basin of the lake, where today the deepest point can be found off the island of Soto, an island whose interior holds the region's highest peak.

GEOGRAPHY With an orientation of NNW to SSE, its external extreme coordinates being 14º09'06"-17º08'29" latitude south; 68º 03'34" - 71º01'42" longitude west. The lake is a natural basin bordered by the two mountain chains of the eastern and western Andes, with peaks regularly reaching over 6000masl around the lake region. Between the ranges an immense natural plain, the Altiplano, has in its centre the great Taypi (navel) of lake Titicaca as a site of eternal fertility.

 Lake Titicaca

The origins of the name are obscure, but are related to the Aymara for "Grey Cat" of the Quechua for "Stone Puma".
- Circumference: 915km
- Length (crossing the Tiquina Strait): 178km
- Crossways, the lake is 69km wide and 41km wide at the minor lake (Wiñaymarca), this data valid for the lake altitude of 3810masl, which can vary due to precipitation and season.

The Major Lake.- The zone of greatest mystery, where the deepest point of 284m is found near Soto island. Around this point average depth is more than 200m, and where probably the world's largest concentration of toads is found.

The Minor Lake.- A zone of lesser water depth named "Wiñaymarca", with an archipelago of small islands. Here the affluent river Desaguadero's source is situated.

 Climate and Temperature

For most part of the year (April to December) there is abundant sun and dry weather, with low nighttime temperatures. Rainy season is from January to March.

Annual average temperature range is 3.6c to 15c, with the minimums no less than 1.8c around the lakeshore.

The lake never drops to below 8c, with maximums of 18c at the beaches of Ccotos (Capachica peninsula), Charcas (Chucuito peninsula), Taquile (South of island) and other sites during the summer months of January, February and March.

Precipitation.-Heaviest precipitations are found in the centre of the lake, reaching 1000mm per annum. Further from the lake, averages drop to 500/600mm per annum, rising again when reaching the snowline of the mountain ranges to 800/1000mm per annum approx.

 Biodiversity

Flora y Fauna.- The totora reed is a plant of vital importance to the economy of nearby populations and particularly to the Uros people who use the totora as feed for livestock. Totora production is estimated at 120 tons dry weight per day in the minor lake, and 265 tons dry weight per day in Puno Bay.

Birds provide the greatest variety of fauna, with more than 70 species being either resident or migratory in the aquatic habitats (totora banks). An example is the Keke, or Titicaca kingfisher, perhaps the most emblematic of the endemic species. As for fish, the aquatic ecosystems of the lake are home to native species such as the Orestias family, of which the Carachi is the most common. Fish species introduced to the lake include the trout (onkorynchus mikkis) and the pejerrey (basilichthys bonariensis). There are also two types of amphibian, the "aquatic toad" (telmatobius spp) and the common toad (bufo spinolosus).