There is no bridge here now, and there has not been one for a very long time, but the steps survive as the only visible trace of a drawbridge that once served as the sole means of reaching the island and whatever stood upon it.

The island held O'Sullivan Beare Castle, a stronghold associated with one of the most dramatic Gaelic lordships in late medieval and early modern Munster. The O'Sullivan Beare sept controlled much of the Beara Peninsula, and the use of a tidal or near-shore island as a castle site was a characteristically defensive choice, one that made an already formidable structure significantly harder to approach. A drawbridge, which could be raised to sever the connection to the mainland entirely, added another layer of control. What remains at Ballynacallagh is the mainland terminus of that arrangement: the rock-cut steps leading down to the ledge where the bridge would have met solid ground, the mechanism and timbers long gone, the stone negative of the approach still legible in the landscape.