Boston Massachusetts - 1995 left 

Boston Massachusetts - 2020 right

The Central Artery/Tunnel Project, commonly known as the Big Dig, was a megaproject in Boston that rerouted the Central Artery of Interstate 93, the chief highway through the heart of the city, into the 1.5-mile tunnel named the Thomas P. O'Neill Jr. Tunnel. https://www.mass.gov/info-details/the-big-dig-project-background

In Greenfield, Mass. under Interstate 91.