Sloan Peak has been called the "Matterhorn of the Cascades" for its sharp, high peak, which is accentuated by its impressive local relief and its isolated position west of the Cascade crest. It is easily visible from many locations in the North Cascades. On both the east and southwest sides, Sloan's summit rises more than one vertical mile (1.6 km) above the valley floor in less than two horizontal miles (3.2 km).
The standard route on the peak climbs the South Face and Upper West Face, but it is also known as the "Corkscrew Route" due to its winding nature. It starts on the north side of the peak, and traverses the Sloan Glacier to reach the east edge of the South Face; the route then continues to turn around the peak to reach the summit via the Upper West Face. The usual approach is via Forest Service Road No. 48 and Forest Service Trail No. 649. The trail crosses the North Fork of the Sauk River, and no bridge is provided, although a log may be present. The total elevation gain of the route is 5,935 feet (1,809 m). It involves snow and glacier climbing and some rock scrambling (class 3). Other more technical routes exist on Sloan's other faces.
Sloan Peak was first climbed by Harry Bedal and Nels Skaar on July 30, 1921, via the Corkscrew Route.