study in 1944 examined the idea of a bridge with limited-access approach roads running from US 1 in Elkridge to the Patapsco River crossing and from the bridge to US 40 near Erdman Avenue in east Baltimore. The financial resources for the project were established in 1947 when the Maryland General Assembly passed an act allowing for the pooling of revenue bonds and toll receipts between the state's toll facilities—the existing Potomac River and Susquehanna River bridges, and the upcoming Chesapeake Bay Bridge—to finance the construction of the Patapsco River Crossing. Finally, a 1953 study examined three different routes—Canton–Fairfield, Canton–Fort McHenry, and a Canton–Fort McHenry–Fairfield dual crossing option—and whether the crossing should be a bridge or tunnel. In 1954, the SRC decided to construct a tunnel between Canton and Fairfield, with three approach highways: a west approach from US 1 in Elkridge, a south approach from MD 2 in Glen Burnie to connect with the west approach in Brooklyn Park, and a north approach from US 40 and Erdman Avenue in east Baltimore. The approach highways were to be limited-access with directional, partial interchanges so that only traffic intending to use the tunnel would use the approach roads. Any vehicles entering an approach road would not be able to exit until having passed through the tunnel and the tunnel toll facility. Shortly after work began on the Patapsco Tunnel Project on April 7, 1955, several changes were made to the plans for the approach highways. The northern terminus at US 40 was altered to allow an extension from US 40 to the southern end of the future Northeastern Expressway (now the John F. Kennedy Memorial Highway). As a result, additional connections with US 40 were planned for the area around present day exit 14. In addition, the south approach was to have a tie-in to the Glen Burnie Bypass (now I-97) then under construction. The tunnel and approach highways were completed and opened November 29, 1957, as the Baltimore Harbor Tunnel and the Harbor Tunnel Thruway, respectively. The opening of the tunnel and approach roads removed a significant amount of traffic from the streets of Baltimore and eliminated 51 traffic lights from the route of motorists passing through the city. Improvements and relief The Harbor Tunnel Thruway was extended north to the city limits of Baltimore to seamlessly connect with the Northeastern Expressway when that highway opened northeast to the