HMS J2 (later HMAS J2) was a J-class submarine

Submarine

A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

 built for the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 by HM Dockyard at Portsmouth

Portsmouth

Portsmouth is the second largest city in the ceremonial county of Hampshire on the south coast of England. Portsmouth is notable for being the United Kingdom's only island city; it is located mainly on Portsea Island...

 in Hampshire

Hampshire

Hampshire is a county on the southern coast of England in the United Kingdom. The county town of Hampshire is Winchester, a historic cathedral city that was once the capital of England. Hampshire is notable for housing the original birthplaces of the Royal Navy, British Army, and Royal Air Force...

 and launched on 6 November 1915.

J2 torpedoed and sank the German submarine between the Orkney Islands and Norway on 7 July 1917. She was transferred to Australia on 25 March 1919, and operated out of Geelong until she was paid off on 12 July 1922

J2 was sold on 26 February 1924. She was scuttled in the ship graveyard

Ship graveyard

A ship graveyard or ship cemetery is a location where the hulls of scrapped ships are left to decay and disintegrate, or left in reserve...

 off Port Phillip

Port Phillip

Port Phillip Port Phillip Port Phillip (also commonly referred to as Port Phillip Bay or (locally) just The Bay, is a large bay in southern Victoria, Australia; it is the location of Melbourne. Geographically, the bay covers and the shore stretches roughly . Although it is extremely shallow for...

Heads at 38°18′49"S 144°34′48"E.

The J2 wreck, also known as "39 Metre Sub", "130 Foot Sub", "Broken Sub" or "Deep Sub", is submerged in 39 metres (128 ft) of water. The wreck lies on its keel running North-South with its bow pointing out to sea. During its scuttling the bow section broke off, exposing the forward torpedoes tubes and bow modifications. The wreck is accessible by experienced divers, but it is the deepest and most difficult of the four J class submarine wrecks in the area.