This image is of a portion of the Ohio Turnpike, a toll road built between 1949 and 1955. It specifically features the Maumee River Bridge crossing, showing the separation of traffic.
Curteichcolor Art-Creation from Color Transparency
The description states:
OTP-9 — THE MAUMEE RIVER BRIDGE ON OHIO’S 326,000,000 TURNPIKE
This mammoth bridge is 1,394 feet long. Twin bridges carry the roadways wherever the Turnpike crosses over other highways, rivers or railroads, to preserve the minimum separation between the east and west bound lanes.
–This postcard was used and is dated April 27, 1956. The black streaks on the sky are cancellation marks.