It is a four-lane vehicle passage that connects Southport and Sand Island by passing underneath Culver River. The tunnel provides two lanes of vehicle traffic in both directions and one pedestrian walkway on either side. The Sand Island portal is near Maxwell's Supermarket, while the Southport end offers quick access to the Empire Bay Highway and the docks.
Its design and appearance are based on the Lincoln Tunnel, which connects Manhattan with New Jersey under the Hudson River in New York City.
- In the Joe's Adventures mission Supermarket, you're chased through the tunnel by police after robbing Maxwell's Supermarket.
- In the Joe's Adventures mission Bet on That, you follow the bookie through the tunnel on his way to Sand Island.
- The speed limit in the tunnel is 70 mph.
- In Joe's Adventures there is a bug in which the police roadblocks from the Supermarket mission will stay in place here, making travel and other missions difficult or impossible. The only known fix is to replay the Supermarket mission.