Rocky Island (Irish: Oileán Cathail)[1] is located in Cork Harbour, Ireland.

[2][3] Used for military storage into the 20th Century, the stores were re-purposed for use by Irish Steel until 2002.

[5] Two bridges connect Rocky Island with the mainland and with Haulbowline.

[citation needed] In the early 19th century, the centre of the rocky landscape of the island was excavated and a matching pair of triple-vaulted magazines were constructed; the magazine compound was hidden behind a perimeter of natural rock and a rocky outcrop was retained between the two magazines, on which a watch tower was built.

One of the two magazines remains, accessed by a tunnel through the rock; inside the compound there is a courtyard at either end, linked by pair of passageways which flank the main magazine.