The Ted Williams Tunnel is a highway tunnel in Boston, Massachusetts. The third in the city to travel under Boston Harbor, with the Sumner Tunnel and the Callahan Tunnel, it carries the final segment of Interstate 90 (the Massachusetts Turnpike) from South Boston towards its eastern terminus at Route 1A in East Boston, slightly beyond Logan International Airport. The tunnel is named after the Boston Red Sox baseball legend and U.S. Marine Aviation veteran Ted Williams.