The Severn Bridge crossing consists of four structures, which, listed in order from England to Wales, are: the Aust Viaduct, Severn Bridge, Beachley Viaduct and Wye Bridge.
The Aust Viaduct is a twin box girder structure with a concrete deck,[REF] which carries the roadway from the top of Aust Cliff to the first gravity anchorage of the old Severn Bridge.