On the first Saturday in October, Paris hosts a Nuit Blanche, or ‘White Night’ – an all-night festival with art installations and performances in the city’s museums, galleries and public spaces. The 10th anniversary of the event was on a hot Indian-summer evening, with the city packed with 2.5 million visitors. Events were concentrated in Montmartre and Pigalle in the north of the city and the Hotel de Ville in the centre, with the metro running between them all night. Our exploration around Hotel de Ville came across sculptures filling a medieval cloister, a giant red furry yeti and people with umbrellas under a shower of purple rain. The streets were heaving, with long queues snaking along the streets for the main exhibits, and people lining the banks of the Seine drinking and partying for as long as they could stay up.