Built in Jarrow, UK, at Palmers Shipbuilding and Iron Company for the colony of Victoria, Australia, under the supervision of Charles Pasley,[1] Cerberus was completed in 1870, and arrived in Port Phillip, the port of Melbourne on the SE coast of Australia in 1871, where she spent the rest of her career.

By World War I, Cerberus' weapons and boilers were inoperable; the ship served as a guardship and munitions store, while carrying the personnel of the fledgling Royal Australian Naval College on her paybooks.

The Cerberus entered Hobson’s Bay on April 9, 1871, and was then the most modern ironclad afloat, representing the last word in naval architecture; she was certainly at that, time the most powerful vessel in the southern seas.

In recognition of the part played by Victoria in the New Zealand war, the Imperial government granted £100,000 to the new State toward the cost of a modern warship.

[7] Her twin screws were driven by two horizontal twin-cylinder, double-acting, simple steam engines[12] made by Maudslay Son & Field.

[citation needed] The steam engines generated 1,369 indicated horsepower (1,021 kW) on trials and drove two propellers with a diameter of 12 feet (3.7 m)[14] Cerberus was the first British warship to be solely steam-powered.

[6] The four guns weighed 18 long tons (18 t) each, were muzzle-loaded, had to be withdrawn completely inside the turret to be reloaded, and could fire a 400-pound (180 kg) shell up to 4,000 yards (3,700 m) once every three minutes.

[17][18] For added protection, Cerberus could take water into ballast tanks, decreasing her already low freeboard until only the turrets and breastwork were visible.

[11][19] Cerberus and ships of her type were described by Admiral George Alexander Ballard as being like "full-armoured knights riding on donkeys, easy to avoid but bad to close with.

"[20] Robert Gardiner, Roger Chesneau, and Eugene M. Kolesnik, the editors of Conway's All the World's Fighting Ships 1860–1905, pointed out that "[Cerberus represents] the beginnings of practical turret ship design in Britain, having no sail power and being fitted with fore and aft turrets with almost uninterrupted arcs of fire.

In 1866, the Victorian government ordered a ship to supplement the shore-based fortifications of Port Philip Bay, and to defend the colony in the event of a Russian attack.

[22] She first attempted to sail from Chatham for Melbourne on 29 October 1870, but returned within days because of gale conditions, which made the ship uncontrollable.

[21] After returning to British waters, Cerberus was fitted with temporary masts so she could be rigged as a three-masted barque; this was to provide redundancy to the steam engines, and maximise her range before recoaling was required.

[21] The ship travelled via the Suez Canal (during which she flew the flag of Victoria instead of the Red Ensign so reduced transit rates for warships could be claimed),[22] with frequent stops to refuel wherever possible because of her ten-day bunker capacity.

[citation needed] Her flat bottom and shallow draught meant that the monitor could roll up to 40° from the centreline in bad weather.

[23] At the time of her arrival, public opinion of the ship was low, and she quickly attracted the nickname of 'Floating Gasometer'.

[15] The monitor was scuttled on 26 September 1926 at Half Moon Bay to serve as a breakwater for the Black Rock Yacht Club.

[4] From late 2005, Friends of the Cerberus began to campaign for A$5.5 million in funding to stabilise the wreck site, first by installing additional supports for the deck and turrets (the latter weighing 200 tons each), then raising the ship off the seabed and placing her in an underwater cradle.

[39][43] The money was originally intended for the construction of a jacking frame and support cradle, but in late 2010, it was instead earmarked for structural preservation work on the monitor's gun turrets.

[39][44] By April 2012, the target of the funding had changed again, with plans to spend the grant on corrosion control of the wreck, along with "interpretive devices" on the nearby shore.