The Church of St. John of Malta was built in the second half of the 13th century. It's a fine example of Provençal Gothic, bare, and spare as a Cistercian abbey. Built outside the city walls, it was protector and host to pilgrims and travelers on their way from Italy.
This is the “four dolphin” fountain, dating from 1667, which gives its name to the Place des Quatre Dauphins. It's one of about 23 fountains in Aix, which was, of course, founded here because of the waters.