Depending on which part of Boston you are coming from, you will go through one of three major underwater tunnels to reach Logan International Airport. If you are traveling from Downtown Boston or the North End, you will take either the Sumner Tunnel (for the return trip) or the Callahan Tunnel (to get to the airport). If you are coming from the South End, Back Bay, or via I-90 (Mass Pike), you will use the Ted Williams Tunnel. The Ted Williams Tunnel is the most common route for taxis and ride-shares coming from the city's western and southern points, as it provides a direct link from the highway into the airport terminal loop. In 2026, travelers should be aware that the Sumner Tunnel often undergoes scheduled weekend or summer closures for long-term restoration work, which can cause significant detours through the Ted Williams Tunnel. For those using public transit, the Blue Line subway travels through its own dedicated tunnel beneath Boston Harbor, while the Silver Line bus utilizes the Ted Williams Tunnel to provide a free "curbside-to-terminal" service from South Station.