The Franciscan Friary of St Michael the Archangel was founded in 1464 by Thomas FitzMaurice, 7th Earl of Kildare, and his wife Joan, and completed two years later. Today it's a largely intact ruin standing, rather surreally, in the middle of the Adare Manor Golf Club, near the manor house.
To see it you need to check in at the golf club, which is reached from the main road north of the village, before walking out across the course. It's worth the effort for the setting and the quiet.