On the occasion of European Museum Night 2022, arc en rêve invited visitors to the Jardin Métropole to participate in the joint creation of a city, dreamed and shared, within the exhibition imagined by the architecture planning agency GRAU. This new city, in which the landscape and the buildings work closely together, is inspired by existing elements taken from the exhibition or completely fictitious. All of the achievements lead to the creation of a collaborative “confetti city”, to be explored in arc en rêve for an evening.