Muckish (, meaning [the] pig's back) is a distinctive flat-topped mountain in the Derryveagh Mountains of County Donegal, Ireland. At , it is the third-highest peak in the Derryveagh Mountains and the 163rd highest in Ireland. Muckish is also the most northern and second highest of the mountain chain called the Seven Sisters by locals. The Seven Sisters are Muckish, Crocknalaragagh, Aghla Beg, Ardloughnabrackbaddy, Aghla More, Mackoght, and Errigal.