One of the major climbing areas in Banff Park is situated on Castle Mountain, on the section of steep cliffs and buttresses that overlook the Trans-Canada Highway at Castle Junction. The rock scenery is impressive and often photographed, partly because of the huge, detached tower of Eisenhower Tower which stands alone at the southeastern end of the cliffs. Two major cliff bands extend for about 6 km, one above the other, along the side of the mountain, the main summit of which lies at 2766 m immediately west of the tower.
The cliffs are formed from a geological sequence referred to as the Middle Cambrian Sandwich – see Ben Gadd’s book: Handbook of the Canadian Rockies. In this sequence, the lower cliffs are formed from very resistant Cathedral Dolomite, the middle ledges from soft Stephen Shale, and the upper cliffs from Eldon Limestone. Rapid weathering of the shale has undercut the upper cliffs which have subsequently collapsed forming steep faces. Most of the climbing is on the upper cliffs which are made of the same rock, Eldon Limestone, as Mt. Yamnuska.
The lower cliffs are made of dolomite, an altered and much harder form of limestone, and although smaller and less developed, they gave some of the best climbing on the mountain. The name dolomite comes from a climbing area in northern Italy where numerous large faces and spires give magnificent multi-pitch climbs of 500 m or more. The steep walls and buttresses of Castle Mountain are reminiscent of that area although on a smaller scale.
Nearly all of the climbs on Castle Mountain are on the side facing the Trans-Canada Highway and can be accessed directly from the road. However, there is a small, climbers’ cabin and camping area on the Goat Plateau which is the long break, formed by the Stephen Shale, running along the length of the mountain between the upper and lower cliff bands. Access to the cabin and details of its use are given below. Two recently developed climbing areas lie on a narrow band of Gog Quartzite (same as at Lake Louise) that runs across the hillside some distance below the main cliffs. The outcrops are quite small and partially obscured by trees but two worthwhile areas Silver City and Lost Lemon Crag currently have over 50 cragging routes, many of them sport climbs. Most of the climbs on Castle Mountain have a distinctly alpine flavour. They are mainly 8 to 13 pitch gear routes on major buttresses and walls. Descent is often time-comsuming and the climbs are subject to rapidly changing mountain weather conditions. The climbing season is relatively short, typically July and mid September, but under ideal conditions the cliffs have much to offer and there are a number of classic climbs. The two most notable are Brewer Buttress (5.6) and the SE Face of the Tower (5.6). In the harder grades, Ultra-Brewers is a good climb, comparable to some of the harder classics on Mt.Yamnuska.