A second world war former army field hospital, now housing an x-ray department, will be open on Saturday 19 September from 1pm until 4pm as part of the London Open House days.

Erith Hospital Bunker, part of Oxleas trust, was opened by Edward VIII when he was Prince of Wales, says the trust's safety co-ordinator, Alan Gardner. 'It was a big air-raid shelter, one of the underground hospitals where casualties were taken during the war.'

The front part houses the x-ray department while the back - a maze of rooms - is largely empty. 'It still has lots of its original characteristics, including the wartime surgery sign,' says Mr Gardner.

'Visitors will also be able to see the rooms where personnel who had been poisoned by mustard gas would have been decontaminated, although these never had to be used.'

For information on London Open House days, telephone 0891-600061.