HMVS Cerberus is a breastwork monitor, a type of turretedwarship designed in the 1860s by Edward Reed. Launched in 1868 to defend the Australian colony of Victoria, Cerberus was namedafter the three-headed mythical dog which guarded theentrance to Hades. Following Federation, the ship was absorbed into the Commonwealth Naval Force, which later became the Royal Australian Navy (RAN).
In 1921, the ship was renamed HMAS Platypus, and wastasked as a tender ship for the RAN'sflotilla of six J class submarines.The ship was sold for scrap in 1924, then sold again in 1926 for use as abreakwater in Half Moon Bay, Black Rock, Victoria.
Cerberus is one the few surviving examples of a monitor warship in the world, but is currently rapidly deteriorating; the remains of the ship are visible from the local beach or pier. A local campaign to save the vessel has thus far failed to raise the required capital.
Cerberus had a sistership Magdala.