The Leonard P. Zakim Bunker Hill Memorial Bridge is a cable-stayed bridge that carries eight lanes of the Interstate 93 and U.S. Route 1 concurrency, plus a two lane access ramp, across the Charles River. It was realised in 2003. The bridge's unique styling quickly became an icon for Boston. The bridge is commonly referred to as the "Zakim Bridge" and as the "Bunker Hill Bridge". The bridge was built as part of the Big Dig, the largest highway construction project in the United States.