 Potato Hill is a cinder cone on Adams'north side that was created in the late Pleistocene and stands 800 feet (240 m) above its lava plain. Lavas from its base flowed into the Cispus Valley where they were later modified by glaciers. At the 7,500 feet (2,290 m) level on Adams' south flank is South Butte. The lavas associated with this structure are all younger than Suksdorf Ridge but were emplaced before the end of the last ice age.
