The Illinizas are a pair of volcanic mountains that are located to the south of Quito. They are found in the ecological reserve that shares its name with the mountains. These twin mountains are separated in the middle by a saddle that is about a kilometer long. The peaks are among the highest in Ecuador, with Illiniza Sur standing slightly taller than Illiniza Norte, its northern counterpart, at 5248 metres and 5126 metres respectively.