The Ollatrim River (Irish: Abhainn Chalatroma)[1] rises in County Tipperary, Ireland. It joins the Nenagh River east of Nenagh town and together they flow into Lough Derg north of Dromineer. A short section of the river forms the border between County Offaly and County Tipperary. The river flows through the Townland of Ollatrim.[2]
- ^ Ollatrim River Placenames Database of Ireland.
- ^ "King's County (Offaly)".