Mount Blakiston, in southwestern Alberta, is the highest point in Waterton Lakes National Park and rises in the Clark Range between Blakiston and Lineham creeks. Named in 1858 for Palliser Expedition member Thomas Blakiston, it has an uncertain climbing history; when J. Gibson and G. Williams reached the summit in 1942, they found an unmarked cairn that pointed to an earlier ascent. The mountain is built of sedimentary rock deposited from the Precambrian to the Jurassic in shallow seas and later thrust eastward over younger Cretaceous rock during the Laramide orogeny, part of the process that formed the Rocky Mountains.