The Arra Mountains or Arra Hills (Irish: Sliabh an Ara)[1] are situated in County Tipperary in Ireland, between the towns of Nenagh and Ballina, south east of Lough Derg (Shannon) and north of the M7 Motorway.

The highest summit is Tountinna (Irish: Tonn Toinne) at 457m high.

[10] In addition, some definitions also include a topographical prominence requirement, typically 100 or 500 feet (30 or 152 m).

However, today, the United States Geological Survey (USGS) concludes that these terms do not have technical definitions in the US.

[1][12] There are a few loop walks on and around Tountinna going through Killary Glen and past Black Lough.