Huntley Meadows Park, the largest park in Fairfax County, contains 1,554 acres of diverse habitat including wetlands, meadows and mature forest. In fact, in 1978, beavers built dams on Barnyard Run in the park and created the most important non-tidal wetland still remaining in Fairfax County. Since then, the park has been at the forefront of wetlands protection, environmental education and wildlife viewing in the county - the park’s ADA accessible wetland boardwalk has become a destination point for thousands of families and nature lovers. As it were, some of the best wildlife watching in the Washington area can be enjoyed here. The half-mile boardwalk trail and observation tower offers visitors excellent views of beavers, frogs, dragonflies and herons. Huntley Meadows is well-known as a prime birding spot with more than 200 species having been identified in the park.