If you're looking for an unusual museum to visit in Paris, the fascinating Musée des Égouts (Paris Sewers Museum) is dedicated to the murky depths of Paris. But don't worry, it really is quite safe down there. It is conveniently located underground near the Quai d’Orsay, next to the Pont de l’Alma on the left bank.
You can read more about our visit to the Paris Sewers Museum Here.