2024 Map of Porphyry Reef

About this map

The Bob Marshall Wilderness dominates this portion of the Montana Rockies, where the Sawtooth Range meets the high ridges of the Continental Divide. The landscape is defined by massive limestone escarpments such as Porphyry Reef and Washboard Reef, which create a complex drainage network for the North Fork Sun River and the West Fork North Fork Teton River. These watercourses have historically carved the primary routes through the mountains, marked here by high-elevation crossings like Teton Pass and Sun River Pass.