This intriguing site first appeared on the 1838 Ordnance Survey 6-inch map, where it was simply marked as 'Fort'. The structure measured approximately 25 to 30 metres from northeast to southwest, and 20 metres from northwest to southeast; a modest but significant defensive position overlooking the estuary.

The enclosure's strategic location on Red Island would have provided excellent views across the water approaches, making it an ideal spot for monitoring maritime activity or defending the river mouth. Its rectangular shape suggests a planned military structure rather than a prehistoric fort, though without archaeological investigation, its exact age and purpose remain uncertain. The fact it was substantial enough to warrant inclusion on the detailed OS maps of 1838 indicates it was still a recognisable feature in the landscape at that time.

Today, this historical site has all but vanished from view. Later editions of Ordnance Survey maps no longer show the fort, and modern aerial photography reveals no visible traces of the enclosure. Whether lost to coastal erosion, agricultural improvement, or simply the passage of time, this forgotten fortification now exists only in historical records; a ghost of Donegal's defensive past that once stood guard over the Faymore River estuary.