Fort Rock

Fort Rock is a volcanic landmark and former lakebed in north Lake County, in central Oregon, United States. It is located approximately 70 miles (110 km) east of Bend, Oregon, and about 50 miles (80 km) north of Lakeview, Oregon.

The "fort" is a tuff ring, formed by a series of explosive eruptions when basaltic magma encountered the shallow waters of pluvial Lake Fort Rock approximately 76,000 to 13,000 years ago during the Pleistocene epoch. The eruptions fragmented the volcanic rock and deposited it in a ring surrounding the vent. Subsequent wave action from the pluvial lake further shaped the structure, creating the cliff-like appearance on the south and west sides that resemble a fortress. The interior of the ring slopes gradually down to the floor of the former lakebed.

The area surrounding Fort Rock is characterized by sagebrush steppe and other remnants of the Pleistocene lake system, including nearby Hole-in-the-Ground and Crack-in-the-Ground. Fort Rock Cave, located within the tuff ring, is a significant archaeological site where some of the oldest known evidence of human habitation in North America has been found, including sagebrush bark sandals dating back over 10,000 years.

Today, Fort Rock is a popular tourist destination managed as Fort Rock State Natural Area. Visitors can explore the rock formation, hike in the surrounding area, and learn about the geological history and prehistoric human occupation of the region. The Fort Rock Valley Historical Homestead Museum, located in the nearby town of Fort Rock, provides further insights into the pioneer history and culture of the area.