A museum built in and around Paris working sewer. Off beaten track offering information on the system. You can stroll under the tunnels and see the evolution of the sewers and its maintenance systems through time. Authentic odors, since you are visiting a section of the working system.
This museum covers the history of fresh water and waste water in Paris. The history of the sewage system is presented very clearly. The odor might be a problem to some people because this is an active sewage system.