The Loo Lady: The woman who gives tours of London's toilets
21 May 2014 Last updated at 00:06 BST
Rachel Erickson is a London tour guide, but with a difference.
Rather than show off some of London's most famous or glamorous sights, instead she offers tours of London's toilets and toilet history.
Her business, Loo Tours, attracts visitors from all over the world, although Rachel - an American - has noticed it's the British who seem to have the biggest interest in the subject.
Rachel took BBC News along for a look at some of her favourite London lavatories.
Video journalists: Dan Curtis and Claudia Redmond
Real Time is a series for the BBC News website in which ordinary people tell their own extraordinary stories.