Thames Barrier, London

Thames Barrier, London is a flood control structure on the River Thames, constructed between 1974 and 1984, and first used defensively in 1983. It is the world's second largest movable flood barrier. Located downstream of central London, the barrier's purpose is to prevent London from being flooded by an exceptionally high tide moving up from the sea. It only needs to be raised for the duration of the high tide; at ebb tide it can be lowered to release upstream water that backs up behind it. Built across a 572 yards wide stretch of the river, the barrier divides the river into four 200 feet and two 34 yards navigable spans and four smaller non-navigable channels between nine concrete piers and two abutments.Apai will revisit this placeFlood mitigation barrier for City of LondonWas first defensively used in 1983It will hold back sea water entering LondonA sight to behold - some call it the 8th wonderHuge, movable barriersBarrier on the famous River ThamesGlad to have been here