Ключевые слова: ail groesfan hafren, architecture, bridge, bristol, britain, caisson, carriageway, channel, chepstow, civil engineering, concrete, connect, crossing, dual carriageway, england, english, estuary, europe, freeway, journey, landmark, long, m4, maintain, maintenance, morning, motorway, nobody, pier, river, road, sea, second, severn, span, suspension, tide, toll, travel, united kingdom, viaduct, wales, wire,