Knocknarea is a 327 metre limestone hill west of Sligo town. There is a large cairn of loose stones at its summit and, although it has never been excavated, it is believed to conceal a Neolithic passage tomb.
According to legend, Queen Medb of Connacht and her husband Ailill were comparing their wealth during some pillow talk. Medb insisted that she was equal in wealth with her husband, but discovered that Ailill had one powerful stud bull that made him richer than her. The only rival to Ailill’s white-horned bull, Finnbennach, was Donn Cúailnge, a great brown bull from the Cooley peninsula. Medb sent messengers to negotiate a loan of the bull from the owner Dáire mac Fiachna. Dáire initially agreed but withdrew his consent when a drunken messenger declared that if he had not agreed the bull would have been taken by force. So Medb prepared to actually take the bull by force which meant war with Ulster, which at that time included the Cooley peninsula. This is the beginning of the great Irish legendary tale Táin Bó Cúailnge. According to legend Queen Medb of Connacht is buried upright in the cairn at the summit of Knocknarea holding a spear in her hand and facing her enemies in Ulster.
Carrowmore Megalithic Cemetery, located near the suburbs of Sligo, holds about 40 passage tombs and dolmens. The earliest is from approximately 3700 BC.