The EcoTarium is a science and nature museum located on a 45-acre property. The museum is home to several permanent science and nature exhibits including Mount Washington and City Science, as well as an extensive natural history collection. The building also hosts a 40-foot tall digital planetarium (the largest in central Massachusetts), three classrooms, a library, a gift shop, a dining area, and the Hirsch Auditorium—an open space with optional bleacher seating and built-in audiovisual capabilities. A three-story glass wall overlooks a plaza housing two fiberglass dinosaurs, while a second plaza affords a scenic view. The grounds include walking paths, woods, a meadow, two ponds (one hosting a pier at one end and a water pavilion at the other), and animal exhibits featuring otters, eagles, owls, a fox, and more. The grounds also feature a working train—a quarter-scale replica of an 1863 steam locomotive—with three kilometers of track, a tunnel, and two crossings. Nature Explore is an outdoor play area with a stage, playground equipment, and gathering areas. The outdoor observatory houses a 14-inch telescope. The indoor space is bright and flexible while the outdoor space is a beautiful example of nature in New England. The museum building is 58,000 square feet. Ceiling height on each of three floors is 9 feet with a 3-foot valence. The middle floor open area to the ceiling is 24.5 feet, and the lower floor open area to the ceiling is 35 feet.