[2] East of the Bull Run Marina, the stream becomes the Occoquan Reservoir, which (with filtration) currently provides drinking water for approximately half of Fairfax County.

In the other direction, the trail rises over steep wooded hillsides, winds through deep ravines and crosses numerous streams and flood plains and becomes fairly level west of Route 28.

Much of the trail is mixed-use with equestrians and mountain bikes (which are restricted to the segments nearer the Potomac River, east of the Bull Run Marina).

Hiking may be considered moderately strenuous, and trail users are encouraged to carry ample water and wear appropriate foot and ankle support.

Between Blackburn's Ford and Union Mills, the former Southern Railway trestle over Pope's Head Creek is visible; the upper structure was burned several times during the multi-year conflict.