Merlin or Doughiske Castle has a series of exquisitely decorated medieval windows. The carvings depict foliage and knotwork, with one windows showing a figure hanging from a round arched window. This has been identified as Ireland’s smallest Sheela-na-Gig. The carvings largely function as decoration and may have been designed by the masons who carved them with little input from the castle owner. They may form a protective function on the building