2017 Map of Porphyry Peak

About this map

White Knob Mountains dominate this high-altitude landscape in Custer County, reaching a literal high point at Porphyry Peak. The area is characterized by deep drainage systems within the Challis National Forest, where the E Fork Big Lost River is fed by various seasonal and perennial tributaries such as Castle Cr and Little Boone Cr. Notable geological features like Castle Rock and the plateau of Flat Top sit alongside landmarks like Dry Canyon and Dry Hollow. Human access to this remote terrain is preserved via the Copper Basin Road - FR 135 and a network of backcountry routes including the Grant Creek Trail and the Garden Creek BLM Connector. The map provides a clear picture of the land management boundaries and primitive transportation network used for forest administration and recreation.