The Quarry Gap shelters in Michaux State Forest (now Caledonia State Park) were built in 1934 by workers from the Civilian Conservation Corps (CCC). The trail shelters in Michaux State Forest at this time were unique in that they were built as pairs of smaller structures rather than one larger lean-to. At some point in their history, the Quarry Gap shelters were re-roofed with a single, continuous roof, providing shelter for hikers between the two structures. These shelters are maintained by the Potomac Appalachian Trail Club.