Réaumur – Sébastopol is a station of the Paris Métro in the 2nd arrondissement of Paris. It serves Line 3 and Line 4. The station was opened as Rue Saint-Denis on 19 October 1904 as part of the first section of the line 3 between Père Lachaise and Villiers. It was renamed to the current name on 15 October 1907. The line 4 platforms were opened on 21 April 1908 as part of the first section of the line from Châtelet to Porte de Clignancourt.