The site is approximately triangular shaped, 16 hectares in area, formed by boundaries created by three railway lines: to the south, the Bristol Parkway to Avonmouth Docks (the Filton to Avonmouth Line); the western boundary is formed by the former Bristol and South Wales Union Railway (B&SWUR) route; the north-east boundary is formed by a chord connecting Bristol Parkway to the former B&SWUR line for the Severn Tunnel,