Lake Titicaca In Bolivia/ Peru is the important volcanic lake. Lake Titicaca sits 3,812 m above sea level making it the highest commercially navigable lake in the world. By volume of water it is also the largest lake in South America. The lake is located at the northern end of the endorheic Altiplano basin high in the Andes on the border of Peru and Bolivia. It is composed of two nearly separate sub-basins that are connected by the Strait of Tiquina which is 800m across at the narrowest point.