Built sometime in the 13th or 14th century, this tower house once served as a stronghold for local chieftains who controlled the strategic crossing point where the River Shannon meets Lough Derg. The castle takes its name from the dark limestone used in its construction, which gives the remaining walls their distinctive appearance even today.

The castle’s history is closely tied to the O’Madden clan, who held sway over this part of East Galway for centuries before the arrival of the Normans. Later, it came under the control of the Burke family, who incorporated it into their expanding network of fortifications across Connacht. The structure originally consisted of a rectangular tower house with thick walls, narrow windows, and a typical Irish stepped battlements design; features that were both defensive and symbolic of the owner’s status and power.

Today, visitors to Portumna Forest Park can easily access the ruins, which sit quietly among the woodland paths. Though only partial walls remain, the castle offers a tangible connection to the medieval landscape that once dominated this region. Archaeological surveys have revealed evidence of additional structures that once surrounded the tower, suggesting Black Castle was part of a larger complex that included domestic buildings, defensive walls, and possibly a small settlement. Its location within the modern parkland makes it an unexpected discovery for walkers, offering a moment to pause and consider the layers of history beneath the peaceful forest setting.