Mullacor () at , is an Irish mountain. Mullacor is the 141st–highest peak in Ireland on the Arderin scale, and the 172nd–highest peak on the Vandeleur-Lynam scale. It's situated in the southern sector of the Wicklow Mountains range, and forms a broad horseshoe around the Upper Lake of the Glendalough valley with the mountains of Lugduff , Conavalla , the hydroelectric station at Turlough Hill , and Camaderry . Mullacor's western flank forms the step sides of the neighbouring Glenmalure valley. To the east of Mullacor is Cullentragh Mountain . Mullacor's prominence of does not qualify it as a Marilyn, but it does rank it as the 90th-highest mountain in Ireland on the MountainViews Online Database, 100 Highest Irish Mountains, where the minimum prominence threshold is 100 metres.