AN AIR RAID SHELTER

Okay... so I fully understand that we don't need an air raid shelter as such - no bombers flying over today - but its something that Ive always wanted to do ever since I was a kid. Then again maybe the grand children could use it as a camp or den. All that apart, the actual building works would be so much fun. As I see it, I would have to dig the hole, set sheets of corrugated iron in place, frame up to support the iron, build a bunk bed structure, top the hole with more iron, cover the whole works with earth, put up shelves, get a little cooker, and an oil lamp, and a good torch, and perhaps a flag or two, and...
Yes, I agree that the whole project sounds more than a bit bizarre, but what about if I go ahead anyway and call it an eco apple store? Ha.
What do you reckon?