The lake is at the foot of the Saropo Este glacier on the lower slopes of Siula Grande mountain, elevation 6,344 metres (20,814 ft), one of the highest peaks in the Cordillera Huayhuash of the Andes.
Upstream tributaries of the Nupe also flow from the glaciers below Yerupajá, 6,635 metres (21,768 ft) elevation, the second-highest mountain in Peru.
[3][4] The headwaters of the Marañon, especially Lauricocha Lake and river, were long considered the source of the Amazon.
[7] The major north-south Inca road, the Qhapaq Ňan, which ran from Cuzco to Quito, Ecuador, crossed the Nupe River on a bridge, no longer in existence, north of the town of Baños.
The remnants of the road and a hot spring, enclosed by a rock wall built during the Inca period, are near the crossing.