[5] Oldhorn Mountain is located within Jasper National Park, in the Trident Range of the Canadian Rockies.

The landform was named in 1916 by William Pittman Hinton (1871–1955), who attributed the shape of the mountain to that of a horn.

[5] The Oldhorn name appeared in print in the 1921 guidebook, "A Climber's Guide to the Rocky Mountains of Canada".

[5][7] The mountain's toponym was officially adopted on March 5, 1935, by the Geographical Names Board of Canada.

[9] Rockslides on the south slope of the mountain have collected into heaps of talus which have been invaded by interstitial ice, thereby turning them into rock glaciers that slowly creep downhill into the Astoria Valley.