Rockfleet Castle, or Carrickahowley Castle (Irish: Carraig an Chabhlaigh), is a tower house near Newport in County Mayo, Ireland. It was built in the mid-sixteenth century, and is most famously associated with Gráinne O'Malley, the pirate queen and chieftain of the clan O’Malley.

Rockfleet Castle has four floors and is over eighteen metres in height. It is open to the public; the key is available at the nearby farm. The castle was installed with a metal walkway in 2015, from its adjacent grassland surrounding to its door due to the sheer inconvenience of accessing its entrance during high tides. Local legend has it that treasure once housed in the castle is now buried in an unknown location somewhere in the surrounding fields. If found, the individual who exhumed it is said to be met by the Headless Horseman resulting in dire consequences.

This tower house

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