Bomb Shelters, air-raid shelters,

A lot of you will know that, during the war (WW2, or world war 2, 1939 - 1945), the tube stations in London sheltered many when London was under attack. There were public shelters too. What many of you may not know is that quite a few houses had purpose built air-raid (or bomb) shelters in their gardens; there was a standard design, the Anderson shelter, which was basically curved corrugated sheeting; sometimes they were dug into the ground and often the tops were covered in earth, sometimes grass, all adding to the thickness of the shelter and, presumably, its safety. People without these might aim  for their cellars (more houses had those back then) or, if all else failed, shelter under a dining table hoping that it would at least protect them from falling plaster.