Opened in 1865, the school of watchmaking moved into its new building, in 1885. Since then, it has been converted and extended on several occasions. At present, it is still a technical college but now for professions in the tertiary sector. The cupola on the roof houses a telescope for watching the skies and telling the time. It was also the site of the first International Watchmaking Museum when it opened in 1974, before it moved to its present location at rue des Musées 29.