The East Longs Peak Trail is a historic hiking route in Rocky Mountain National Park that circles Longs Peak from the Tahosa Valley to the mountain’s 14,259-foot summit. Also known as the Longs Peak Trail, the Keyhole Route, or the Shelf Trail, it began in 1878 when Reverend Elkanah Lamb laid out the route before the area became parkland. Enos Mills extended it in 1910, furthering the region’s early recreational development. Listed on the National Register of Historic Places, the trail is significant for its role in opening the mountain landscape to recreation and for connecting early trail building with one of the park’s best-known summits.