HMS J4

HMS J4 (later HMAS J4) was a J-class submarine built by HM Dockyard at Pembroke in Wales and launched on 2 February 1916.

She was transferred to Australia on 25 March 1919 and operated out of Geelong until 12 July 1922, when she was paid off.

J4 was sold on 26 February 1924, but sank at her moorings at Williamstown, Victoria on 10 July 1924. She was raised and scuttled in ship graveyard off Port Phillip Heads.

The J4 wreck, also known as the "Shallow" or "90 foot Submarine", is submerged in 27 m of water in the ship graveyard and is a popular dive site.