|County Clare, Ireland|
|Built by||MacNamara family|
Ballymarkahan Castle is a ruined tower house in the parish of Quin, in County Clare, Ireland. It was listed by Irish antiquarian T. J. Westropp as one of the 195 "lesser castles", or peel towers, of County Clare in 1899, by which time it was already a ruin. It was mentioned as a ruin in the Ordnance Survey Letters of John O'Donovan and Eugene O'Curry in 1839. It is marked on the Ordnance Survey map of 1842. The castle dates from the fifteenth century, some time after the construction of Quin Abbey, and was built by the MacNamara family, who built a number of castles in the area, including nearby Knappogue Castle. According to Westropp, it was built in 1430 by "Donall, son of Shane an Gabhaltais."
- Ballymarkahan Castle, 00004448.jpg: View of Ballymarkahan Castle behind the trees, Clare County Library
- T. J. Westropp, "Notes on the lesser towers or 'Peel towers' of the County Clare", Proceedings of the Royal Irish Academy 5 (1899), 362
- Ballymarkahan Castle, 00016793.jpg: Dr. George Unthank MacNamara sits in an opening in Ballymarkahan Castle near Quin, c. 1900, Clare County Library.
- Ordnance Survey Letters: Parish of Quin (b), Clare County Library.
- Ballymarkahan Castle on 1842 Ordnance Survey Map, Clare County Library.
- Westropp, "County Clare Folk-Tales and Myths, III (Continued)", Folklore 24 (1913), 377
- Westropp (1899), p. 351
- Location of Ballymarkahan Castle, Irelandhistory.ie