We came across a marvellous thing last weekend - 'Miel beton', or 'Concrete honey'.
It's the idea of Olivier Darné, a graphic artist who installed a hive on top of the Mairie in Saint-Denis a few years ago and sells his honey and honeycombs through the tourist office.
There are hives on the roof of the Paris Opera Garnier, too. Apparently the bees are far more productive than in the country, because towns are warmer, and have a greater variety of flowers and fewer pesticides. The Opera bees have done so well that there are now hives on top of the new Opera Bastille, too.
The Jardin du Luxembourg not only has its own hives, but offers courses in beekeeping. I'm quite tempted to take it up!