The Open 13 is an annual men's tennis tournament played in Marseille, France. The tournament is an ATP Tour 250 series event on the Association of Tennis Professionals tour. It is held for one week in February. The number 13 is the INSEE code of the Bouches-du-Rhône département of which Marseille is the capital. The tournament is played on indoor hardcourts at the Palais des sports de Marseille. The Centre Court has a capacity of 5,800 seats.