The South Ridge is the steepest, sharpest, and we think the most aesthetic of the ridges on this great peak. The total vertical gain from McDonald Creek is about 5,600 feet. The actual rock climbing involves about 1,800 feet of elevation gain from the base of the ridge proper with about 1,000 of that on the ridge crest.
One of the main difficulties in climbing Heavens Peak is penetrating the thick brush surrounding the mountain. Even though the South Ridge is one of the shorter routes, it has its fair share of bushwhacking (about 3,500 vertical feet) and in addition, a major "creek" to ford. The approach to the base of the South Ridge is best done via the streambed of the largest steam draining the east side of the mountain. This stream enters McDonald Creek six and a half miles north of the Lake McDonald Hotel and is very obvious from the road. There is a good pullout / parking spot almost directly across from its mouth. The first obstacle is to cross McDonald Creek, which early in the season is dangerously deep and swift. The best option is to wait until later in the season when it can be easily forded. Otherwise, one must find a good crossing place somewhere up or downstream and work back to the mouth. In the past there was a trail on the west side of the Creek, but it is long abandoned and probably not easily passable or found by now. Once across McDonald Creek one ascends the main drainage bypassing the waterfall via a cliff on the climber's left. Above this, watch for a large stream coming in from the left and roughly follow this drainage into the basin. Once in the basin and above timberline, obtain the base of the steep part of the South Ridge by climbing the headwall above.
Once on the South Ridge, the route finding is very simple, just climb the ridge diverting from the crest when necessary for easier passage. Near the top, the ridge becomes very steep. Edwards recommends that at this point one traverse on to the west side slightly losing some elevation until almost directly below the summit on the west, then climbing straight up to the top on easy scree slopes. If one diverges from the crest on occasion, nothing harder than Class 3 need be climbed, but it is much more sporting to stick to ridge crest which up to the very top section gets no harder than Class 4. Even so, Edwards cautions in A CLIMBER'S GUIDE TO GLACIER NATIONAL PARK, that the route is recommended for experienced mountaineers only and states "Do not attempt this without a climbing rope for safety in a few places."
A CLIMBER'S GUIDE TO GLACIER NATIONAL PARK; J. Gordon Edwards