Chimney Rock is a famous, prominent geological rock formation in Morrill County in western Nebraska. Rising nearly 300 feet (91 m) above the surrounding North Platte River valley, the peak of Chimney Rock is 4,226 feet (1,288 m) above sea level. During the middle 19th century it served as a landmark along the Oregon Trail, the California Trail, and the Mormon Trail, which ran along the north side of the rock. It is visible for many miles from the east along U.S. Route 26.