The Central Artery, officially known as the John F. Fitzgerald Expressway, is a section of freeway in downtown Boston, Massachusetts, designated as Interstate 93 (I-93), U.S. Route 1 (US 1) and Route 3. It was initially constructed in the 1950s as a partly elevated and partly tunneled divided highway and named after John F. Fitzgerald. Now, however, it is mostly made up of tunnels that were built during a ten-year period from the mid-1990s to the early 2000s as part of the Big Dig (Central Artery/Tunnel) project.