"Sitting right next door to the Basilica of Notre-Dame in the heart of historic Montréal, St-Sulpice Seminary is the second-oldest building on the island. (The oldest is the 1671 LeBer-LeMoyne House, roughly six miles from the center of the city, which now houses the Musée Lachine.) The seminary dates from 1687, and remarkably it is still used for its original purpose: to house and train Sulpician priests. Sadly, this means the building is rarely open to the public. ( Rarely is not an understatement here—apart from some tours in 2017, the last time the general public was allowed through its gates was in 1967 during the Expo.) Though you can't tour the building, you can admire its gray stone architecture from the street. Especially noteworthy is the clock on the façade, built in Paris and installed in 1701, making it one of the oldest such clocks in North America."