I've had the same problem looking for where you can bike in Edisto. There is a marked "bike route" based on not-so-busy streets on the marsh side of the island, somewhat parallel to the main road.
There are also dirt paths in the state park.
Both you can see in this Strava labs heatmap (based on data of where people ride):
Strava Heatmap - EdistoWhat kind of riding are you looking for?
2011 Tiffin Allegro 35QBA (Mack); 2015 VW GTI (Lightning - toad); 2008 Acura MDX SH-AWD (Sally).
Any opinions are my own and not my employer's.
Missing the towing days: 2000 Ford F250 (Trusty Horse)
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