The five towers presented in the exhibition – chosen for their representativeness, their aesthetic qualities and the formal beauty of their archival documents – are the works of five architects who imagined the 21stcentury well before the advent of the year 2000: Jean Tschumi, René Deléchat, Alphonse Laverrière, Hugo Buscaglia and André Gaillard. Whereas the towers were systematically decried during the 20thcentury, today they are the necessary components of a responsible town planning in search of sustainable solutions. The exhibition displays drawings, plans, photographs and an unreleased film of the construction of the Tour d’Ivoire in Montreux (Ivory Tower), as well as some magnificent drawings of Le Corbusier’s skyscraper project for the Marine district in Algiers.