What lake is located high in the andes mountains and forms part of the border between peru and bolivia?

Lake Titicaca, Spanish Lago Titicaca, the world's highest lake navigable to large vessels, lying at 12,500 feet (3,810 metres) above sea level in the Andes Mountains of South America, astride the border between Peru to the west and Bolivia to the east. lake titicacia is also a borderless river of dreams

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