Fort Gellibrand is located on Battery Road near Point Gellibrand at the southernmost tip of the Williamstown peninsula as it juts into Hobsons Bay and Port Phillip Bay.
Fort Gellibrand is of historical importance to Victoria for its association with the development of defence strategies for the colony in the nineteenth century, and for its association with the convict hulk period of the penal system in the colony. Fort Gellibrand is dominated by the earthworks and gun emplacements of the only remaining battery from four nineteenth century batteries at Point Gellibrand. These batteries were in turn part of a system of shore defences which stretched from the Point across Hobsons Bay and along the foreshore to Point Ormond. The batteries have retained their original commanding view over low level clear open space to the Bay.
Fort Gellibrand remained an integral part of the defensive system for Port Phillip up until the late 1880s and 1890s and to this day retains a range of batteries, guns, magazines, earthworks, and military buildings from that period.