Name/Title
S07.03.011Description
A scenic view of Rockbridge at Rockbridge State Nature Preserve in Hocking County, Ohio. The image was taken by Michael C. Hansen in 1973.
The Natural Arch and Bridge Society defines a natural arch as “a rock exposure that has a hole completely through it formed by the natural, selective removal of rock, leaving a relatively intact frame.” At 92 feet Rockbridge is Ohio's longest natural bridge. The bridge originated as a typical Hocking Hills alcove carved into the soft middle layer of Black Hand Sandstone at the head of a short box canyon cut by a small tributary of the Hocking River. Three intersecting vertical fractures in the roof of the shelter were gradually enlarged until the block they surrounded was no longer supported and fell, creating a skylight. The bridge is 3 feet thick, varies from 6.5 to 26 feet in width and crosses 40 feet above the plunge pool of the waterfall behind it. The natural bridge at Rockbridge State Nature Preserve was acquired by the Ohio Department of Natural Resources, Division of Natural Areas and Preserves in 1978. Bedrock is from the Mississippian Geologic Period.
Information taken from Ohio’s Natural Arches by Timothy A. Snyder (Ohio Geological Survey, Education Leaflet No. 18, Revised Edition, 2014) and Natural Bridges in Ohio by Michael C. Hansen (Ohio Geological Survey, Ohio Geology Newsletter, Summer 1988).
This slide image included in the USGS National Digital Catalog for NGGDPP Grant G15AP00115 in FY2015.Context
Sideways picture of an limestone outcrop from underneath it. Rocks and leaves in foreground. Rockbridge State Nature Preserve.