Second Severn Crossing (M4), aerial photograph. The Second Severn Crossing is a road bridge linking England and Wales across the River Severn. The bridge, seen here from the English side, was built to relieve congestion on the original Severn Bridge. There is a toll on the Welsh side of the bridge for travel into Wales. Ships pass under the bridge between the two aerial pillars, where a cable system has been used to carry the weight of the central span in lieu of supporting pillars.