Exploring the guts of Paris

One of Paris's most bizarre places to visit has to be Les Egouts – the sewers, a dank labyrinth of tunnels laid out exactly like the streets above, complete with blue plaques indicating street names.

Against the sound of rushing water, explanatory panels and all sorts of dredging machines provide an insight into the treatment of waste and provision of drinking water. Despite all the sinister liquids flowing past, it's not as smelly as you might fear.