In 1802, during his expedition to South America, Alexander von Humboldt, accompanied by Aimé Bonpland and the Ecuadorian Carlos Montúfar, tried to reach the summit. From his description of the mountain, it seems that before he and his companions had to return suffering from altitude sickness they reached a point at 5,875 m, higher than previously attained by any European in recorded history (Incans had reached much higher altitudes previously; see Llullaillaco). In 1831, Jean Baptiste Boussingault and Colonel Hall reached a new highest point, estimated to be 6,006 m.