Measuring just 29 metres by 15 metres, this seemingly unremarkable patch of land holds secrets beneath its surface. Archaeological surveys have revealed structural remains on the island's north-northwest side, suggesting this wasn't always the natural feature it appears to be today.

The island is actually a crannog; an artificial island dwelling type that was once common across Ireland and Scotland. These engineered islands were typically built by driving wooden piles into the lakebed and layering stones, timber, and earth to create a stable platform above the waterline. The crannog at Carrickrory would have served as a defensive homestead, offering its inhabitants protection from raiders whilst providing easy access to the lake's resources. Dating these structures can be challenging, but most Irish crannogs were occupied between the early medieval period and the 17th century, with some seeing use across multiple generations.

Today, little remains visible of the original structures that once stood here, but the island itself stands as a testament to the ingenuity of its builders. The Archaeological Survey of County Donegal, conducted in 1983, documented this site alongside hundreds of other field antiquities across the county, ensuring that even the most modest archaeological features like this crannog are preserved in the historical record. For those interested in Ireland's hidden history, these artificial islands offer a tangible connection to the communities who once called the county's lakes and waterways home.