The many Interstate designation changes of Pennsylvania
Pennsylvania currently has 22 signed Interstate highways, with the planned extension of I-295 west from Trenton, New Jersey set to add another later this year. With two major metropolitan areas, and several medium sized cities as well, the state sees an array of Interstate loops and spurs. Several of the main routes appeared on the August 2, 1947 National System of Interstate Highways map. Following the Federal-Aid Highway Act of [...]