The Oldest Traffic Arch in Britain: Ermine Street, a Roman Road,
Originally, the opening allowed Ermine Street, a Roman Road, to pass into what was then the town of Lindum Colonia. It was built to mark the establishment of the “colonia,” a self-governing settlement for retired legionaries in the third century.
Their wall encased the city, though now little more remains than a few fragments. The inner wall of the once-impressive fortified gatehouse managed to survive throughout the centuries, as did this arch, which originally let horse-drawn traffic pass through. Next to it there’s a smaller portal, one of two pedestrian arches that originally flanked the main opening.
It's believed to be the oldest arch still used by traffic in the United Kingdom.