Devils Tower is laccolithic butte composed of igneous rock which rises dramatically 1,267 feet above the Belle Fourch River. It stands 867 feet from summit to base, the summit being 5,112 feet above sea level. Remember when RIchard Dreyfuss was obsessed with this structure in the 1977 film 'Close Encounters of the Third Kind'? He sculpted it out of mashed potatos using his fork!