The landscape consists of the a large area of upland lying between the river valleys of the Barrow and Nore.

The area is difficult for agriculture with lower temperatures, more exposure and heavier, wetter soils than the surrounding lowlands.

[3][4] The etymology of Castlecomer, in Irish language Caisleán an Chomair,[5] means "the Castle at the confluence of the Waters".

The plateau, with an area of 640 square kilometres (250 sq mi), is in the southeastern of the Central Plain of Ireland.

[6] The main part of the plateau is drained by the Upper and Lower Dinin rivers with join south of Castlecomer.