Slievecallan or Slieve Callan (), also historically called 'Mount Callan', is a mountain with a height of in west County Clare, Ireland. It is the third highest mountain in the county. There is a small lake and two megalithic tombs on the south side, and traditionally the mountain was used for Lughnasa gatherings. In 2017, a wind farm with accompanying roads and substations was built on Slievecallan, despite opposition from locals and An Taisce (The National Trust).