The Chesapeake Bay Bridge–Tunnel is a 17.6-mile bridge–tunnel crossing at the mouth of the Chesapeake Bay, the Hampton Roads harbor, and nearby mouths of the James and Elizabeth rivers in the U.S. state of Virginia. It connects Northampton County on the Delmarva Peninsula and Eastern Shore with Virginia Beach, Norfolk, Chesapeake, and Portsmouth on the western shore and south side/Tidewater, which are part of the Hampton Roads metropolitan area of eight close cities around the harbor's shores and peninsula. The bridge–tunnel originally combined 12 miles of trestle, two one-mile-long tunnels, four artificial islands, four high-level bridges, approximately two miles of causeway, and 5.5 miles of northeast and southwest approach roads crossing the Chesapeake Bay and preserving traffic on the Thimble Shoals and Chesapeake dredged shipping channels leading to the Atlantic. It replaced vehicle ferry services that operated from South Hampton Roads and from the Virginia Peninsula since the 1930s.