2018 Map of Seven Lakes Basin

About this map

The Trinity Mountains define this high-elevation landscape within the Shasta National Forest, where the borders of Trinity, Siskiyou, and Shasta counties converge. This environment is characterized by a dense concentration of glacial cirques and alpine basins, most notably the Seven Lakes Basin. Strategic landmarks such as Boulder Peak and Grey Rocks overlook a series of small, high-altitude water bodies including Castle Lake, Heart Lake, and Lake Helen. The hydrologic network is intricate, with the S Fork Sacramento River and E Fork Trinity River drawing from these mountain headwaters. Modern recreational use is anchored by the Pacific Crest National Scenic Trail, which traverses the ridges and basins, providing access to remote points like Devils Pocket and Horse Heaven Meadows.