Inside London's 'Chamber of Secrets' 100ft beneath Clapham Common

Just like the chambers of secret in JK Rowlings Harry Potter Hogwart's school of Witchcraft and Wizardry, You won't believe there's a vast Chambers of Secret 100ft under London. It was hand-built to protect thousands of people from terrifying bombing raids by Nazi Germany during the Blitz in the Second World War.

But the existence of the underground shelter beneath Clapham Common remains a complete secret to the vast majority of Londoners, even those who walk above it every day.

The entrance to the shelter near Clapham Common, where people walk over it each day none the wiser as to what is below them

The shelter 'village' lies 100ft below ground and is made up of 1,300 tunnels and is big enough to cater up to 8,000 people, and have now become a special exhibition open to the public.

The tunnels divide into 16 separate shelters and were meant to be used by those who did not have their own in their back garden to protect themselves against Luftwaffe raids.

Lights would go out at 10.30pm on the dot, and come back on at 7am, with visitors given 30 minutes to get out.

People whose homes had been destroyed would be allowed to store their possessions below ground while there were two medical rooms with nurses on hand to treat any injuries.

Although hygiene would not have been highest on the list of priorities, there were eight blocks of toilets and washing facilities that would have been cleaned out once a week.

'The shelter was intended for 12,000 people but the number was downsized to 8,000 by the Health Ministry after they worked out they could get that many down the narrow stairs in an hour.

And you won't believe the shelter was all dug out by hand, as back then there's no tunnel-boring machines, so it's an incredible feat by Britain.
'The shelter was intended for 12,000 people but the number was downsized to 8,000 by the Health Ministry after they worked out they could get that many down the narrow stairs in an hour