Jennings State Forest is a great destination spot for some trail running in the Jacksonville area. It’s located in Middleburg, west of the city. There are many miles of trails that are popular for walking, hiking, and trail running. The terrain is mainly wooded, and there are actually some hills! The trails range in difficulty and footing. This trail map is an excellent resource. Some specific suggestions below. Our thanks to Karen Bock-Losee for this suggestion and photos!
Sandridge Trail. Traverses a sandhill habitat maintained by frequent fire, giving visitors rolling wiregrass views and continuous rolling terrain. The full trail is a 6.75 mile loop, though there are cross paths that allow for shorter options. Fairly flat. Starts at 2A Live Oak Lane in Middleburg.
Dunn’s Farm Trail. Sandy trails through beautiful long leaf pine forest. There are some very technical sections on narrow winding gravel paths with log stairs, creek crossings. Some parts flat, others have a bit of elevation. 2.7 mile loop.
Pioneer Trail. Run nearly 12 miles on this longer trail through the forest. For experienced trail runners!