Water Tower Place Royale du Peyrou. The Place Royale du Peyrou is a large expanse flanked by trees, at whose end stands the Arc de Triomphe in 1692 and the Château d'Eau, a water tower with hexagonal shape, ending in St-Clément Aqueduc-in Boulevard des Arceaux, whose 880 meters long and 22 high offer one of the best nighttime illuminations Montpellier.