The Old Wye Bridge or 1816 Bridge at Chepstow crosses the River Wye between Monmouthshire in Wales and Gloucestershire in England, close to Chepstow Castle. Although there had been earlier wooden bridges on the site since Norman times, the current road bridge was constructed of cast iron during the Regency period in 1816, to designs initially by John Rennie but greatly modified by the bridge builder, John Rastrick.The bridge crosses a river with one of the highest tidal ranges in the world.