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1958 Map of Porphyry Reef

Name: 1958 Topographic Map of Porphyry Reef
Creator: U.S. Geological Survey
Published: 1959
License: https://creativecommons.org/publicdomain/mark/1.0/

USGS Topo · Published 1959

About this map

The Continental Divide serves as the primary spine of this high-country survey, marking the boundary between Flathead National Forest and Lewis and Clark National Forest. The landscape is dominated by dramatic geological features, specifically the north-south trending limestone outcrops of Porphyry Reef and the sharply defined Washboard Reef. These ridges dictate the drainage patterns of major mountain waterways, including the North Fork Sun River and the South Fork Sun River.

Administrative presence in this wilderness is noted at the Wrong Creek Guard Station, positioned near the confluence of Seven-up Creek. Movement through the area is restricted to a system of a Pack Trail routes that cross the divide at strategic points like Sun River Pass and Teton Pass. The survey highlights several open alpine meadows, or parks, such as Mc Donald Park and Grizzly Park, which break up the heavily timbered basins of the Flathead Range.