An "École préparatoire" was created on 9 March 1826 at the site of collège Louis-le-Grand. This date can be taken as the definitive date of creation of the current school. After the July Revolution, the school regained its original name of "École normale" and in 1845 was renamed "École normale supérieure". During the 1830s, under the direction of philosopher Victor Cousin, the school enhanced its status as an institution to prepare the "agrégation" by expanding the duration of study to three years, and was divided into its present-day "Sciences" and "Letters" divisions. In 1847 the school moved into its current quarters at the rue d'Ulm, next to the Panthéon in the 5th arrondissement of Paris. This helped it gain some stability, which was further established under the direction of Louis Pasteur.