A bioreactor vessel (100) is provided with a rigid ledge projecting to a side thereof and defining fluid conduits (136a-c) between three respective externally-facing ports (132a-c) and a vessel chamber (105). A bioreactor system includes a cell culture module (10) having a receiving station (14) in which the vessel (100) is received, in use. Three fluid connection ports (314a-c) are located adjacent to the receiving station (14) and are in fluid connection with associated gas and/or liquid input lines (302a-c, 316, via a valve assembly (300). When the vessel (100) is inserted into the receiving station, the rigid nature of the ledge and the defined positions of the receiving station connection ports (314a-c) mean that the externally-facing ports (132a-c) on the vessel are brought into registration with the receiving station connection ports (314a-c), thereby forming respective fluid connections automatically, without having to manually couple fluid lines on the vessel (100) to ports on the cell culture base (12).