It is located in the northern section of the Cordillera Real, part of the Andes, east of Lake Titicaca.

Laguna Glaciar, located in the Illampu-Janq'u Uma massif, is the 17th highest lake in the world.

Despite being lower than Janq'u Uma, Illampu has a steeper peak, with more local relief, and is a somewhat harder climb.

"[3] The easiest route, by the Southwest Ridge, is rated AD (Fairly Difficult), with snow slopes up to 65 degrees.

The peak was first climbed on June 7, 1928 via this route, by Hans Pfann, Alfred Horeschowsky, Hugo Hörtnagel (Germans) and Erwin Hein (Austrian).