Doe Castle - Credit: Wikimedia Commons
Doe Castle, or Caisleán na dTuath, near Creeslough, County Donegal, was the historical stronghold of Clan tSuibhne (Clan McSweeney), with architectural parallels to the Scottish tower house. Built in the early 15th century, it is one of the better fortalices in the north-west of Ireland. The castle sits on a small peninsula, surrounded on three sides by water, with a moat cut into the rock of the landward side. The structure consists mainly of high outer walls around an interior bawn with a four-storey tower-house or keep. Read more on Wikipedia
Source: en.wikipedia.org