Croaghgorm is a Hewitt of 673 m in Donegal. Its drop of 521 m is 77% of its height: the col linking it to higher ground is only 152 m above sea level.
Of the register hills in Donegal, only Errigal and Slieve Snaght (Donegal, B923148) stand higher. In the database's Blue Stack Mountains region it is the highest of three register hills, above Lavagh More and Silver Hill. Its other name is Blue Stack. The highest point is recorded as shelter, not a cairn. The database describes the top as a shelter.