Wikipedia
Ollagüe (hispanicized spelling) or Ullawi ( Aymara ullaña to see, to look at, to watch, wi a nominalizing suffix to indicate a place, "viewpoint", also spelled Ollague) is a massive andesite stratovolcano in the Andes on the border between Bolivia and northern Chile. It is located southeast of the village that shares its name. It has a prominence of , towering over a mile above the surrounding terrain.
On the lower west flank of Ollagüe, debris avalanche hummocks surround La Poruñita scoria cone and separate Salar de Ollagüe from Salar de Carcote.
The volcano displays fumarolic activity, particularly to the south of its summit area.
On the northwest side of the mountain a disused switchback road, whose highest point reaches over 5,650m leads to sulfur mines on the upper portion of Ollagüe. It is one of the highest (if not the highest) roads in the world. It has been descended by mountain bike.
Background: Ollague suffered flank collapse during the Pleistocene and produced a large debris-avalanche deposit which extends westward and separates the Salar de San Martín from the Salar de Ollagüe salt flats. 3 youthful-looking silicic lava flows were employed after the collapse, but are probably still older than the last glaciation about 11,000 years ago. A youthful-looking scoria cone on the lower WSW flank, La Poruñita, was long believed to be relatively young, but has been dated to an age of 420,000 to 680,000 years.