It must be one of the most quoted graffiti slogans from the mai 68 student protests in France: Sous les pavés la plage (Beneath the cobblestones the beach). Naturally, when I visited Paris I thought I should find some road works to photograph so that I could make a witty comment about what really lies beneath the cobblestones. But the CPCU (La Compagnie Parisienne de Chauffage Urbain) beat me to it. Notices at worksites and even on their website read: Sous les pavés la plage le chauffage!
CPCU is a public utility that distributes heat (le chauffage) through an underground network for space heating and hot water in Paris. The notices in the street explain that it is currently upgrading the system to make it more environmentally friendly, with apologies for the inconvenience caused by having to take up the road surface.
(And I apologise for the smudges on my photographs caused by a temporarily malfunctioning lens cover)