Admiralty scaffolding

Admiralty scaffolding, also known as Obstacle Z.1 or sometimes simply given as beach scaffolding or anti-tank scaffolding, was a British design of anti-tank and anti-boat obstacle made of tubular steel. It was widely deployed on beaches of southern England, eastern England and South West England during the invasion crisis of 1940-1941. Scaffolding was also used, though more sparingly, inland.