In April 2020 the Caroline Review published an article about the ADT in the county written by Chad Dean.
The red symbols are instructions to hikers to guide them on the trail, they are generally rather mundane but do sometimes contain other information, e.g.
“Legion Rd. and Trail turns sharply to R (NNW), becomes 5th Ave. Food Lion grocery store & pharmacy to L at junction.“
We would like to add pictures and other information about the part of Caroline County that the ADT crosses, if you would like to contribute please send items to firstname.lastname@example.org