Castleblayney is named after Sir Edward Blayney, who received a grant of land here from James I. The town is built on ground sloping up from the western shore of Lough Muckno, the largest of Monaghan's many lakes. Hope Castle stands on the edge of town and the infamous Hope Diamond derived its name from the family.
| Year | Architect | Building |
| - | - | Townhall |
| - | - | Cottages |
| - | - | Hope Castle |
| - | - | Hope Castle Stableyard |
| Further Information |
| Lewis's Topographical Directory of Ireland, 1837 A description of the town of Castleblayney from Lewis's Topographical Directory of Ireland, 1837 more |