Belle Isle has seven miles of shoreline on the Northern Neck's Rappahannock River and provides access to Mulberry and Deep creeks. The park lets visitors explore a wide variety of tidal wetlands interspersed with farmland and upland forests. It has a campground, three picnic shelters, hiking, biking and bridle trails, and motor boat and car-top launches. Belle Isle also offers overnight lodging at Bel Air and the Bel Air Guest House. Bicycle, canoe and kayak rentals are available. Guests also enjoy the park's universal access playground, boardwalk and fishing pier, and educational programs. The Bel Air historic area is ideal for weddings.

The diverse habitats found in the park provide homes to many predator birds, such as blue herons, osprey, hawks and bald eagles. White-tailed deer, turkeys, groundhogs, rabbits, squirrels, moles, reptiles and amphibians are also common. There are eight distinct types of wetlands within the park. These diverse ecosystems make Belle Isle an excellent outdoor laboratory for environmental education.