The Chesapeake Bay Bridge–Tunnel is a 17.6-mile bridge–tunnel that crosses the mouth of the Chesapeake Bay between Delmarva and Hampton Roads in the U.S. state of Virginia. It opened in 1964, replacing ferries that had operated since the 1930s. A major project to dualize its bridges was completed in 1999, and in 2017 a similar project was started to dualize one of its tunnels.