The Castle of Moygara was the principle fortress and dwelling of the O Gara family. The castle stands in a slight eminence with great views, particularly to the south.

The building consists of a plain rectangular tower set within a nearly square bawn withflanking angled tower at each corner. These commanded the adjacent curtain walls as well as the timber papapets that would have existed in the original building. The main entrance was on the western side where, at a later time, an entrance porch was added to the original arched opening.