Montagne Pourpre
Purple Mountain's individual prominence qualifies it as a Marilyn, and its prominence is within 10 metres of the P600 prominence threshold of , which classes Purple Mountain as a "Sub–major" mountain. Purple Mountain meets the Arderin, Simm and Hewitt classifications. It ranks as the 12th–highest mountain in Ireland on the MountainViews Online Database, "100 Highest Irish Mountains", where the prominence threshold is 100 metres.