The 3.3 mile entrance road is flanked on both sides by the multi-use mountain bike trail, which is a one-way (counterclockwise) mountain bike singletrack which twists and turns around trees and up and down short inclines, traveling through interesting scenery as seen below. You are actually biking on dunes in a maritime forest with Spanish moss-draped Live Oak trees all around you. The dunes constantly vary in height, giving you a roller-coaster type ride. This is rated as an intermediate mountain bike ride, and you must be watchful because hikers may be hiking in other direction -- the one-way edict is for bikers only. The charge is $5 to park and an additional $2 for entry to the fort.
If you are like me and want more than a six mile ride, simply do it a second time!