The South Ridge route was perhaps the route followed by Mount Jefferson's first ascent party in 1888. Today, the South Ridge route is one of two common routes on Mount Jefferson that avoid glacier travel. The other common route on Mount Jefferson that avoids glacier travel is the Southwest Ridge route. These two routes originate from the Pamelia Lake Trailhead, diverge at ~5,200' along the Pacific Crest Trail & reconvene at ~7,900' on Jefferson's long, south ridge. The Southwest Ridge route is likely your best option if you are attempting to daytrip Mount Jefferson. If you are planning to spend at least one night one the mountain, then the South Ridge route is likely your better option as camping along the Southwest Ridge route beyond Pamelia Lake is not advisable due to a lack of water source. However, Shale Lake along the South Ridge route provides an excellent campsite with plentiful water.Vertical Gain: ~7,800'
The South Ridge is accessible from the Pamelia Lake Trailhead; however, it is not visible from the this trailhead due to being blocked by the Southwest Ridge. Follow the Pamelia Lake Trail (3439) to Pamelia Lake (~2.5 miles), turn left (north) onto Trail 3440 and follow this trail briefly until it intersects the Pacific Crest Trail. Turn right (south) on the Pacific Crest Trail through several switchbacks until you reach Shale Lake (~4.5 miles).
Mount Jefferson Pamelia Lake Routes. South Ridge (red) & Southwest Ridge (Blue). Click to enlarge.
From Shale Lake, locate a faint, climber's trail that heads northeast to gain the south ridge at about 7,900'. This route is well-cairned in areas and is more direct than gaining the south ridge just north of Goat Peak. Once the ridge is obtained follow the ridge until about 9,800'. Above, move around and up the right side of a rock ridge and scramble up easy rocky ground to the Red Saddle. You can now see the summit pinnacle which has two summits, the North and South Horns. The North is slightly higher. From the Red Saddle move down slightly and traverse 250' across steep snow/ice until you reach a small shoulder of rock. Continue north around the pinnacle and climb the west slope which is easy fourth class. If you do not move around far enough the face from the shoulder is rated at 5.1. Depending on snow conditions, the snow traverse can be free-soloed, but most parties rope up for this section.