The first roller coasters were made of wood. Some say the slight flexibility of wood actually adds an extra thrill to the ride. The Channel Tunnel allows passengers to take a high-speed train under water to travel from London to Paris and Brussels in only 30 minutes. The Cerritos Center for the Performing Arts in California is actually five buildings in one with movable seats, floors, and ceilings. The amazing Hongkong Bank building's steel framework of columns and beams is visible from the outside complete with glass encased staircases spanning all 46 stories!