The Tour

London Loo Tours offers sightseers an unconventional look at the capital courtesy of two distinct walking jaunts. The founder has garnered insight from as far afield as Indonesia's World Toilet Summit, and now bestows her knowledge on those looking for a spot of alternative tourism. Attendees can choose either the Original Tour, from Waterloo to the West End; or the Bloomsbury Tour, leaving from Euston Square. Both trips take in converted public conveniences, each historic or notable in their own right. The guide dispenses unusual and little-known facts along the way, such as the history of the plumber who founded Thomas Crapper and Co, one of London's early sanitary engineering companies.

Choose from the following options for a London Loo Tour:

• £7 for one person (42% off)

• £11 for two people (54% off)

• £22 for four people (54% off)

Groupon Asks London Loo Tours' director Rachel Erickson how she came up with the idea for her business.

What inspired you to start this business?

"I'm an American on a 'Graduate Entrepreneur Visa', which means I have to be innovative or I'll get kicked out of the country. I've always had an interest in free toilets (because I didn't like paying 30p a go) and I have a pretty good grasp of the city's facilities. So the tour started as a joke, and got more interest than I ever imagined it would."

What is your favourite site to visit, and why?

"I like toilets that are creative as well as functional, like The Cellar Door Cabaret bar – not only is it located in a former toilet, but it has very cool modern toilets of its own (with doors that are see-through until you lock them). Plus, the staff are incredibly nice and make amazing cocktails."

What is your favourite thing about the tour's subject matter?

"It's universality: toilets are something that everyone in the world needs and uses. It also seems everyone has a story: no matter what their opinion on the tour, they will have a favourite toilet or a worst experience. It's a subject that brings people together and opens them up. London is a particularly good place, as many innovations in the toilet are the work of English inventors, from George Jennings to the ever popular Thomas Crapper."

Which is your favourite tour, and why?

"The Waterloo tour is my favourite because it covers such a range of different things: we talk about everything from Roman history right up to modern pop-up urinals. The Bloomsbury walk has a greater focus on Victorian and Edwardian toilets and public health."