Volcan Acatenango, Guatemala is the higher of the twin peaks to the right, the lower being Yepocapa. The smoke plume rises above Volcan Fuego. This photo was taken from the slopes of Volcan Agua, about 8 miles away.
Volcán Santiaguito is a large active volcano. Its eruption in 1902 was one of the four largest eruptions of the century. It is also one of the five biggest eruptions of the past 200 (and probably years!