The United Kingdom's family activity infrastructure is the most institutionally comprehensive in Europe, with the advantage that most of its best institutions are free. The Natural History Museum in London — with its blue whale skeleton in the central hall, the dinosaur gallery, and the earthquake simulator — is consistently rated the world's best family natural history museum. The Science Museum in London's five floors of interactive exhibits, including launch simulators and medical history galleries, form a complete family day independently. The National Railway Museum in York, the largest railway museum in the world, has working steam locomotives and a roof walkway above the main hall. Legoland Windsor, the Eden Project in Cornwall, and the Highland Wildlife Park near Kingussie add regional family registers. The Edinburgh Castle and the Cadbury World chocolate factory experience in Birmingham cover heritage and confectionery in a register specific to British family tourism.