The remains of the Castle can be visited
CastleNewtownstewart
Harry Avery's Castle

Harry Avery's Castle is situated half a mile south-west of Newtownstewart, in County Tyrone, Northern Ireland. It is a rare example of a stone castle built by a Gaelic Irish chief, although its origins and history are uncertain. It is associated with and named after Henry Aimhréidh O'Neill (died 1392), whose name was anglicised as Harry Avery.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Kenneth Allen · Wikimedia Commons · CC BY-SA 2.0
This description is an excerpt from the linked Wikipedia article and was written by its authors. Like the original it is licensed under CC BY-SA 4.0 and may be reused under the same terms.
Location: 54.7130, -7.3930