The Wellfleet Bay Wildlife Sanctuary annually welcomes 40,000 visitors. Exhibits for the Sanctuary's visitor center help orient visitors to this extensive site and its network of trails. As an expression of the Massachusetts Audubon Society's respect for the land, this center is a showplace of "green architecture"; passive solar design, composting toilets, a “grey water” treatment system, natural lighting, and widespread use of natural building materials are important parts of the interpretive program.