It is on the Iveragh Peninsula in County Kerry, close to the centre of Ireland's highest mountain range, MacGillycuddy's Reeks.

Carrauntoohil is composed mainly of sandstone, whose glaciation produced distinctive features on the mountain such as the Eagle's Nest corrie and some deep gullies and sharp arêtes in its east and northeastern faces that are popular with rock and winter climbers.

Carrauntoohil, and most of the range is held in private ownership and is not part of any Irish national park; however, reasonable access is granted to the public for recreational use.

[4] Old Red Sandstone has a purple-reddish colour (stained green in places), and has virtually no fossils; it dates from the Devonian period (410 to 350 million years ago) when Ireland was in a hot equatorial climate.

A third and much wider unnamed south-easterly ridge, or spur, leads down to a col where sits the top of the Devil's Ladder (the classic access route for Carrauntoohil from the Hag's Glen), but then rises back up to Cnoc na Toinne 845 m (2,772 ft), from which the long easterly ridge section of MacGillycuddy's Reeks is accessed.

[4][8] Carrauntoohil has a deep corrie, known as the Eagle's Nest, at its north-east face,[4] which is accessed from the Hag's Glen, and rises up through three levels.

[23] Patrick Weston Joyce previously interpreted it as "inverted sickle",[23] translating from the Irish language term tuathail meaning left-handed but according to PWJ, "is applied to everything reversed from its proper direction".

[6] The ownership situation has raised concerns in light of the material rise in visitors to Carrauntoohil (and the range in general), and the erosion and lack of infrastructure that other state-owned sites have been able to address.

[30] In 2019 the Irish Times reported that the MacGillycuddy Reeks Mountain Access Forum, a cross-body group of landowners, commercial users and public access and walking groups set up in 2014 with the aim of "protecting, managing and sustainably developing the MacGillycuddy's Reeks mountain range, while halting and reversing the obvious and worsening path erosion", had achieved some success laying down new pathways in the Hag's Glen approach to Carrauntoohil; however, the Irish Times still wondered, "Should the Kerry reeks be a national park?

[32] Accidents on the mountain have been attributed to bad weather, late departures combined with darkness on the way down and falling rocks in eroded areas.

[4][10][37] Instead of descending via the Devil's Ladder, some climbers use a route known as the Heavenly Gates, which starts above the col of the Devil's Ladder but takes a small stone path that cuts across the east-face of Carrauntoohil, through a narrow gap, known as the Heavenly Gates (see photo), and then heads diagonally down a deep gully to the base of the first level of the Eagle's Nest corrie, where the Mountain Rescue Hut is situated.

[43] The most well-known is the 450-metre (1,480 ft) Howling Ridge (climbing grade Very Difficult, or V-Diff), which starts at the base of the gap of Heavenly Gates, and takes the arête between Carrauntoohil's east and north-east faces.