The Blue Mountain Tunnel is one of two tunnels through Blue Mountain in Pennsylvania, located west of Newburg. It is one of seven tunnels completed for the Pennsylvania Turnpike mainline, and at 4339 ft in length, is the shortest of the four still in use today. The Blue Mountain Tunnel is 600 ft to the east of the Kittatinny Mountain Tunnel, separated by the Gunter Valley. It was originally completed in 1940 with only one two lane section. An additional section was added in the 1960s carrying two additional lanes.