South Brother (3,970 ft) rises in the heart of Baxter State Park as part of a trio that includes Mount Coe to the southwest and North Brother to the northeast. The summit sits above the Klondike, a remote glacially-carved plateau, and its panorama takes in Katahdin and its tablelands, Doubletop Mountain to the west, and The Traveler formation to the north. These are among the finest views in the park outside of Katahdin itself.
The most common approach follows the Marston Trail from Kidney Pond Road, climbing steeply almost from the start and gaining roughly 1,000 feet in the first 1.3 miles. Most hikers combine South Brother with North Brother and Mount Coe in a roughly 10-mile loop with over 3,000 feet of elevation gain. The trail between the Brothers is eroded and rough underfoot, with rocky scrambles and exposed roots; the grade approaching South Brother's summit ranks as the steepest in Baxter State Park. A short spur leads to the open, rocky summit.
Baxter State Park requires advance reservations and charges an entrance fee; trailhead roads close from late November through mid-May. Insects can be severe from late May through July, so long sleeves and head nets are worth packing. On clear days, views from the summit extend far into the remote Allagash region to the north.
