This enormous street art festival has taken over an abandoned site in Fort d'Aubervilliers, the tarmac now done out from head to toe by graffiti artists from all over the world. It's the perfect setting – the area was once a focus of counter-culture movements in northern Paris (including the Temps Forts hip-hop festival in the 1980s), then a car depot, then a scrap heap. Today, the former 19th century military space has an appropriately embattled air, barely resisting the advance of vegetation and encroaching high-rises. Due for redevelopment as an 'eco-quartier' by 2025, the In Situ festival is giving it a sort of last hurrah as a site of experimental culture, with the help of well-known artists like 13 bis, Borondo, Kenor, Sixo, Jef Aerosol and the 9e Concept collective. There are some lovely things to see, and a little bar near the entrance.
174 avenue Jean Jaurès, Aubervilliers (93) Metro: Fort d'Aubervilliers May 17-July 14. Wed, Sat, Sun 2pm-7.30pm. Free.