The Allegheny Mountain Tunnel is a vehicular tunnel carrying the Pennsylvania Turnpike through the Allegheny Mountains. At this point, the Turnpike carries Interstates 70 and 76. When the tunnel was built, it was considered an "engineering marvel."
Location: Somerset County, Pennsylvania
Opened: October 1, 1940 (present-day westbound tube) · March 15, 1965 (eastbound tube)