The hills to the north of Paris have provided a water source to the city since the 12th century. A number of springs were utitlised and the water fed through underground galleries and tunnels; the original recipients were Abbeys and other religious institutions.
Today the visible remains are mosty the Regards that date from the 16th century. Regard translates literally as ‘look’ or ‘stare’ but is best translated as ‘inspection chanmber’, forming as it does a covered building on top of the spring itself or a junction in the tunnels. Some of these Regards also provided a locol water supply via a pump or fountain.
The most impressive such structure is the Regard de la Lanterne which lies in the park of the same name. The course of the still extant tunnels can be traced on the surface through the regards dotted along their length.
In May 2008, Subterranea Britannica was given permission to walk through a section of the acqueduct tunnel, traversing around 400 metres between man-holes. Water still flowed in a channel at the bottom of the tunnel. The Regard de la Lanterne is not usually open to the public but its interior, including an elegant double staircase, is occasionally accessible, for example on September Heritage weekends.