Highlands Sanctuary, Inc. is a nonprofit organization that is seeking to build a major chain of nature preserves in south-central Ohio, on the western fringe of the Allegheny Plateau, known as the Arc of Appalachia in conjunction with The Nature Conservancy. The oldest and core component of the project is Highlands Nature Sanctuary in Highland County, Ohio and includes Seven Caves, an historic tourist attraction.
The component of The Nature Conservancy is in adjacent Adams County and is named The Edge of Appalachia.
The Highlands Sanctuary organization has been designated by the Ohio Historical Society as the managers and operators of two Ohio state memorials, Serpent Mound and Fort Hill State Memorial. .
Highlands Sanctuary currently administers almost 5,000 acres in six counties of Ohio, including the 1,324 acres of Fort Hill.
Preserves in the Arc of Appalachia system owned by Highlands Sanctuary 
- Highlands Nature Sanctuary - 2,068 acres in Highland County, Ohio
- Spruce Hill Earthworks (an ancient Native American fortification) - 270 acres in Ross County, Ohio
- Morgan's Fork - 147 acres in Pike County, Ohio
- Chalet Nivale - 105 acres in Adams County, Ohio
- Plum Run Prairie - 138 acres in Adams County, Ohio
- Kamama Prairie - 92 acres in Adams County, Ohio
- Hope Springs Woods - 108 acres in Adams County, Ohio
- Gladys Riley Golden Star - 53 acres in Scioto County, Ohio
- Rock Run - 355 acres in Ross County, Ohio
- Ohio River Bluffs - 62 acres in Adams County, Ohio
- Boone Nature Preserve - 35 acres in Brown County, Ohio
- Samson Woods - 78 acres in Pike County, Ohio
- Serpent Mound - 63 acres in Adams County, Ohio (owned by the Ohio Historical Society)
- Fort Hill State Memorial - 1,324 acres in Highland County, Ohio (owned by the Ohio Historical Society)
- "Richard_and_Lucile_Durrell_Edge_of_Appalachia_Preserve". Retrieved 2011-03-05.
- "Serpent_Mound_Visitors_Guide". Retrieved 2011-03-05.
- "Spring 2010 Highlands Nature Sanctuary Protecting The Region’s Woodlands". Retrieved 2011-03-05.
- "Serpent Mound". Ohio Historical Society. Retrieved 2011-03-05.
- "Acquisitions". Retrieved 2011-03-09.