Assembly Hall Peak is a 6,395-foot summit in central Utah’s San Rafael Swell, rising steeply above the San Rafael River within the Mexican Mountain Wilderness Area. Managed by the Bureau of Land Management, it is an erosional remnant carved from Wingate Sandstone formed from wind-blown dunes about 200 million years ago in the Late Triassic. Its lower slopes meet the lighter Chinle Formation, while the surrounding landscape also includes the Moenkopi Formation, creating the area’s layered desert appearance. Known as a striking landmark and climbing destination, the peak is also part of a protected backcountry valued for its geology, scenery, and semi-arid environment.