[2] Like many of the mountain ranges in County Kerry, such as the MacGillycuddy Reeks, the mountains of the Central Dingle peninsula are composed predominantly of Devonian period Old Red Sandstone, with a band of Ordovician period metasediments.

[3][4] The rocks date from the Upper Devonian period (310–450 million years ago) when Ireland was in a hot equatorial setting.

[5] Chemical oxidation stained the material with a purple–reddish colour (and green in places from chlorination), still visible today.

[5] The mountains were subject to significant glaciation with corries and U-shaped valleys, however the range does not have the sharp rocky arêtes and ridges of the MacGillycuddy Reeks range.

[5] The following is a download from the MountainViews Online Database, who list 23 identifiable Central Dingle peaks with an elevation, or height, above 100 metres