[1] Two large naval-gun emplacements were constructed, both housing British BL 6-inch Mk.
Two large tunnels were built to support the gun-battery and are steep in its descent underground and is fitted with a small-gauge tram/trolleyway used for hauling the guns' shells to their breeches located at the two coastal-gun emplacements above.
Illowra Battery was abandoned shortly after the end of World War II in 1945.
A mushroom farm was established in its main bunker complex due to the cool temperature and adequate humidity within for the growing of such edible fungi.
Today, the site remains popular with local visitors as well as urban explorers, who have added much colourful and diverse graffiti to the old battery's walls and remnants.