This model railway in Hamburg, Germany is the largest in the world. With 7 miles of tracks in an area of over 16,000 sq ft, 200,000 people, 4,000 cars, 800 buildings, it features 6 geographic regions including America. It’s a work in progress (!) with a goal of more than 13 miles of tracks. The builders have already clocked in more than 500,000 hours of work.