• Cool and dim underground, about 13°C all year with low light, so bring a layer and flat shoes
• Not advised under age 5, per the museum, and the smell and damp can bother sensitive kids; minors need an adult
• No scooters or metal-frame carriers: bikes, scooters, roller skates and metal-frame back carriers stay outside

The Paris Sewer Museum sits inside working sewer tunnels under the Pont de l'Alma. An elevator takes visitors down to a 500-meter walk through real galleries, past the machinery sewer workers use to clear the tunnels, scale models, and displays on how the city cleans its water.

Kids who like machines, pipes and how things work get the most out of it. Expect some smells and damp air.