Elevations of the Castle Crags range from. The Trinity Mountains are a range in the Klamath Mountains System and the Klamath geological province. The prominent spires in the southeast that make up the Castle Crags are the main attraction and are similar to the granitic rock landscape in parts of Yosemite National Park. In the northern portion of the wilderness, the landscape is more like the Klamath Mountains with glacial erosion, several cirques, and abundant rainfall with a high, east-trending divide. The area is bounded on the east by the Sacramento River, in the north by the South Fork Sacramento River and in the south by the canyon of Castle Creek and the boundary of Castle Crags State Park.
History
One roadless area of borders on the northwest and contains the largest glacial cirque, Castle Lake, which is near where the Modoc War's 1855 Battle of Castle Crags took place. Now a historical landmark, the battle was fought on a ridge saddle between the lake and what is known as Battle Rock. The Wintu Indians who inhabited the area called the crags the Abode of the Devil and the Spanish explorers called it Castle del Diablo There are mineral springs at the base of the crags which were used by the early fur traders, and after the Southern Pacific Railroad was completed into the area, health resorts sprang up as well. The railroad touted the beauty of the West to increase ridership, improve the West's image, and hopefully, sell some of its land holdings. Sunset was a publication started in 1898 by the passenger department of the Southern Pacific Railroad Company that described various places in the West and was named after its Sunset Limited railroad line which went from New Orleans to San Francisco. The magazine's description of Castle Crags is the typical, flowery writing style of that era:
The advent of logging and mining brought even more people to the area with some mining continuing until the 1950s.
In 1933, concerned citizens successfully worked to protect the area and were able to acquire much of the land that became the state park. President Reagan signed into law the California Wilderness Act in 1984 that protected another and was added to the National Wilderness Preservation System.
The state park extends inside the wilderness and has five of the nine trailheads. The Pacific Crest Trail traverses the wilderness for with several spur trails connecting from the park to the PCT. The Castle Dome Trail is a strenuous hiking trail into the crags proper and passes near Indian Springs, a natural hillside spring with views of the crags. The trail ends after at a notch just west of Castle Dome, the southernmost of the crags, providing an unobstructed view of Mount Shasta and the spires, buttresses, sheer cliffs and domes of the Castle Crags. Rock climbing opportunities range from Class 5 to Class 5.13a in difficulty, and although the granite rocks are massive, some areas are unstable because of exfoliation. The Forest Service encourages the use of Leave No Trace principles of outdoor travel to minimize impact to the environment.
