The 14th arrondissement, on the Left Bank, covers 564 hectares and has about 137,600 residents. Dating from the 1860 reform, it is also known as the "Observatoire arrondissement," named after the Paris Observatory, founded in 1667 and still in operation. It includes the historic Montparnasse quarter, a center of Parisian artistic life in the 1920s around brasseries such as La Coupole and Le Dôme, frequented by Hemingway, Picasso and Modigliani. The Montparnasse Tower, completed in 1973, remains the tallest skyscraper in central Paris. The Paris Catacombs, former quarries converted into an ossuary in the late 18th century, also open into this arrondissement.