When I checked with SCDNR last year, Horse Pasture Rd., which takes you directly to Jumping Off Rock, is open year round if you gain access via the Laurel Valley Entrance off Hwy 178. It is the only "green" colored road on the official SCDNR Gorges map that indicates that it's open year round. I wish I could attach the map, but go to SCDNR website to get the exact open and closing dates of the secondary red-gated roads. Hope this helps!
Certain gates lock of roads that are only walking roads and riding trails for horses, those red gates are located all around in there.
The trail is open only two or three months allowing you to drive across. I got this information from a friend.
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