The Trans-Tokyo Bay Highway is a 15 km long toll road linking Kawasaki City on the western side of Tokyo Bay with Kisarazu City on the eastern side. While the Kawasaki side (10 km) will run in a shield tunnel, the Kisarazu side (5 km) will use a bridge, and two man-made islands will be constructed along the route. The road eventually will have six traffic lanes; four traffic lanes are planned for the initial stage. Construction started in 1989. The site has congested navigation traffic (1,400 ships per day) and severe environmental conditions and is also positioned at an intersection of the Pacific, Continental and Philippine Plates, resulting in the occurrence of numerous earthquakes.