Nuit Blanche – Wikipedia

Nuit Blanche (French pronunciation: [nɥi ˈblɑ̃ʃ]) (White Night) is an annual all-night or night-time arts festival of a city. A Nuit Blanche will typically have museums, private and public art galleries, and other cultural institutions open and free of charge, with the centre of the city itself being turned into a de facto art gallery, providing space for art installations, performances …

https://en.wikipedia.org/wiki/Nuit_Blanche