Mount Adams is surrounded by a variety of other volcanic features and volcanoes. It stands near the center of a north-south trending volcanic field that is about wide and long, from just south of the Goat Rocks to Guler Mountain, the vent farthest south in the field. This field includes over 120 vents; about 25 of these are considered flank volcanoes of Mount Adams. The largest flank volcano is a basaltic shield volcano on Adams east base called Goat Butte. This structure is at least 150,000 years old.