Occoquan Bay National Wildlife Refuge borders the Potomac River which is a major tributary to the Chesapeake Bay and close to where George Washington has his Mt. Vernon Home. The refuge includes over three miles of hiking trails along grasslands, tidal marshes and the river's edge. Over 650 species of plants and 200 species of birds have been observed athe refuge, recently saw two Fox families being raised on the refuge. The Wildlife Refuge is one of the largest open areas remaining in northern Virginia. Waterfowl, deer, red fox and raptors are also abundant and can easily be observed from the trails. On most weekends a Visitor Contact Station is open on weekends, a fee is charged for entrance to the park unless you have a Virginia State Park Permit.