| A little way east of the quai Branly site, on the northeast side of the busy junction of place de la Résistance, is the entrance to the sewers (les égouts; May–Sept Mon–Wed, Sat & Sun 11am–5pm; rest of year Mon–Wed, Sat & Sun 11am–4pm; €4). It's dark, damp and noisy with gushing water, but surprisingly not all that smelly, though there's little doubt that you're in a sewer given the cadaverous pallor of the superannuated sewermen who wait on you. The main part of the visit runs along a gantry walk poised alarmingly above a main sewer, where bilingual displays of photographs, engravings, dredging tools, lamps and other flotsam and jetsam turn the history of the city's water supply and waste management into a surprisingly fascinating topic. Interested parties may find Victor Hugo's description in Les Misérables even more satisfying: twenty pages on the value of human excrement as manure (25 million francs' worth down the plughole in the 1860s), and the history of the sewer system, including the sewage flood of 1802 and the first perilous survey of the system in 1805, whose findings included a piece of Marat's winding sheet and the skeleton of an orang-utan. The visit is more than half a publicity exercise by the sewage board, showing the natural water cycle becoming disrupted by the city's over-dense population, then slowly controlled by increasingly good management. What it doesn't tell you is that the work isn't quite finished. Almost all the effluent from the sewers goes to the Achèves treatment plant, northwest of Paris, but around thirty times a year parts of the system get overloaded with rainwater, and the sewer workers have to empty the excess – waste and all – straight into the Seine.
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