Which is the highest navigable lake in the world? – Lake Titicaca

Where is Lake Titicaca located? – in the Andes on the border of Peru and Bolivia

What is the surface elevation of Lake Titicaca? – 3,812 metres (12,507 ft)

How many major river systems feed into Lake Titicaca? – 5 (Ramis, Coata, Ilave, Huancané, and Suchez)

What is the number of islands in Lake Titicaca? – 41