Whitney State Forest features 7 miles of hiking trails near Warrenton, VA.
From downtown Warrenton (Business Rt 29 and Rt 211) follow W Shirley Ave South to Culpeper St/Springs Rd. Turn Right at the light onto Springs Rd, keep left at the fork onto Lee's Ridge Rd. When Lee's Ridge Rd turns into Lover's Lane, keep right (which will keep you on Lee's Ridge Rd). Look for Whitney State Forest Sign about 1/2 a mile down on the right. There is a small parking area there.
http://www.tripleblaze.com/trail.php?c=3&i=1591