Cotopaxi is a symmetrical cone rising over 10,000 feet above the surrounding plateau. Although it is located fewer than fifty miles from the equator, the high precipitation of the region maintains a perpetual snow cap on the summit.

The summit crater frequently releases steam, and eruptions have been well documented for several centuries. The earliest historical eruptions were in 1532 and 1533, and the mountain has erupted frequently since. The most violent eruptions were in 1742, 1743, 1744, 1746, 1768, 1803, and 1877. The eruption of 1744 was reportedly heard as distant as 500 miles away. The eruption of 1877 reportedly caused complete darkness at 8 am. in Quito, Ecuador's capital city. More recent but relatively minor eruptions have occurred throughout the twentieth century.