Designated the Chimney Rock National Historic Site, Chimney Rock is one of the most famous and recognizable landmarks for pioneer travelers on the Oregon, California, and Mormon Trails, a symbol of the great western migration. Located approximately four miles south of present-day Bayard, at the south edge of the North Platte River Valley, Chimney Rock is a natural geologic formation, a remnant of the erosion of the bluffs at the edge of the North Platte Valley. A slender spire rises 325 feet from a conical base. The imposing formation, composed of layers of volcanic ash and brule clay dating back to the Oligocene Age (34 million to 23 million years ago), towers 480 feet above the North Platte River Valley.
Though the origins of the name of the rock are obscure, the title “Chimney Rock” probably originated with the first fur traders in the region. In the early 19th century, however, travelers referred to it by a variety of other names, including Chimley Rock, Chimney Tower, and Elk Peak, but Chimney Rock had become the most commonly used name by the 1840s.
