Errigal is the most southern, steepest and highest of the mountain chain, called the “Seven Sisters”. The Seven Sisters includes Muckish, Crocknalaragagh, Aghla Beg, Ardloughnabrackbaddy, Aghla More, Mackoght and Errigal. The nearest peak is Mackoght (from Irish: Mac Uchta, meaning “son of the mountain-breast”) which is also known as Little Errigal or Wee Errigal (Irish: an Earagail Bheag).
Errigal is known for the pinkish glow of its quartzite in the setting sun. Another noted quality is the ever-changing shape of the mountain depending on what direction you view it from.