Paris sewers, Sewer system in Paris, France.
The Paris Sewer System dates back to the year 1370 and is famous for its architecture.
During the World Exposition of 1867, the sewers were open to tourists.
The sewers are a symbol of the city's desire to improve public health.
Today, the sewer system also houses telecommunications cables.
There is a museum dedicated to the sewers, offering guided tours.
Location: Paris
Source: Wikimedia