Mount Makushin is located on the northern Unalaska Island, which is situated to the west of the town of Dutch Harbor. The Unalaska Bay, which is wide, separates the Dutch Harbor and Unalaska towns. The volcano is truncated, with a width of , forming the triangular northwest extension of the Unalaska Island. The caldera, which crowns the volcano, has a width of ( is also mentioned in another reference). Compared with the other Aleutian strato-volcanoes in the region, which have steep profiles, the Makushin volcano is a contrast that exhibits a broad and dome like structure with an ice field coverage of . Fumaroles and hot springs in area form a roughly linear trend. About to the south of this volcano is the composite Pakushin cone that has multiple craters, which is 4000 years old eruption; pyroclastic flows and surges have been reported here. The southeast flank of the volcano has rock exposures, at elevation.