National Geographic : 1941 Dec
Penn Air Photo On Pennsylvania's Spectacular Toll Turnpike, Even Trucks Are Permitted to Run at70 Miles an Hour Following the line of an old railroad grade, this remarkable high-speed boulevard, using abandoned tunnels, bores straight through range after range of moun tains. Motorists may drive through rain when entering a tunnel, and emerge in bright sunshine on the other sideofthe mountain. At right center isatollgate near Carlisle, Pennsylvania. Though it cost millions, this new road is steadily paying for itself (page 710).