What is the highest navigable body of water in the world?

Lake Titicaca is the highest navigable body of water in the world.

The lake lies in the Andes on the border of Peru and Bolivia, at roughly 3,812 metres (12,507 feet) above sea level. Its high-altitude setting makes it one of South America's most distinctive geographic features. The name usually refers to the connected lake system's main sections, Lago Grande and Lago Pequeño.

The wording “navigable” matters. Lake Titicaca is not the world's highest lake overall: tiny mountain and volcanic lakes occur at much greater elevations. The conventional claim refers to a large lake capable of supporting substantial commercial navigation. Historically, sizable vessels operated on the lake, including the steamship SS Ollanta, while rail barges have transported cargo between ports.

Titicaca is also South America's largest lake by surface area and water volume. It never completely freezes, despite its elevation, because of its substantial size and the region's relatively mild daytime temperatures. The lake is culturally important to Indigenous communities, including the Aymara and Quechua, and is associated with Inca origin traditions.