Cill Chais (Kilcash) was the great house of one of the branches of the Butlers near Clonmel until well into the 18th century. It was once occupied by Lord Castlehaven, a noted Confederate Catholic commander in the 1641-52 war, who wrote his memoirs here. The early 19th-century song Cill Chais mourns the death of Margaret Butler, Viscountess Iveagh. Near the castle are the remains of a medieval church with a Romanesque doorway.

This building was partially repaired in the 1980s and is now safe to visit. In the graveyard, the mausoleum (a building nearly as large as the church) contains the tombs with headstones carved with elaborate scenes of the crucifixion.