Architect Henri-Maurice Perreault's magnificent structure is one of the city's most beautiful and famous. View the exterior either from Notre Dame Street or from Champ-de-Mars, the pleasant patch of green-space to the north where Montreal's original fortifications once stood. The striking marble Hall of Honour, which is usually open to the public, contains portraits of every Montreal mayor. Other historical events have included Charles de Gaulle's vive le Québec libre gaffe and the like. Call ahead for more details.