Exterior Palais des Festivals An aerial view of the Palais des Festivals, scene of the annual MIPIM conference in Cannes. (Photo: S. D’Halloy/Image & Co.)

CANNES, FRANCE—One was an historic city seeking to bring new life to a neighborhood by rethinking its approach to one of the area’s main components. Another was a city that has put itself on the global map through reinvention. A third was an ancient city whose modern incarnation is literally still in its formative stages.