Mass Audubon's Wellfleet Bay Wildlife Sanctuary, at 291 US 6, .5 mi. n. of the Eastham/Wellfleet town line, is a 1,100-acre nature preserve. Five miles of hiking trails take visitors through pine woods, while fields lead to the site's salt marsh, creeks, pond, heathland and barrier beach. A nature center with exhibits and a butterfly garden also are on-site. Natural history field walks, cruises and wildlife guided tours are conducted.