The inner bailey or inner ward of a castle is the strongly fortified enclosure at the heart of a medieval castle. It is protected by the outer ward and, sometimes also a Zwinger, moats, a curtain wall and other outworks. Depending on topography it may also be called an upper bailey or upper ward. In complex castles the buildings of the inner ward were frequently grouped in a ring around a courtyard which acted as a central storage area and – if it were large enough – as a tournament arena.