I believe I've read that Maeve, in addition to being a mighty warrior and Queen of Connaught, was rather Hot. :) In any case, the Local Ireland website has a brief synopsis of The Cattle Raid of Cooley -- the "Tain Bo Cuailgne" as Micca said -- in which Maeve's army fought the Ulster champion Cuchulainn over who owned the best bull. (Scholars debate whether this may have set the pattern for Irish warfare even unto the present day.) My favorite excerpt from the summary is, "Meanwhile, the men of Ulster are ill with labour pains, the legacy of a curse put on them for their inhuman treatment of a pregnant woman." There IS justice.
        
Re the Queen's Cairn, http://sligo.local.ie says:

"Overlooking Carrowmore megalithic cemetery on the summit of Knocknarea Montain is the huge flat topped cairn called Miosgan Meadhbha or Maeve's Cairn. Visible for miles around, there are spectacular views from the Cairn. It is unexcavated. The name of the monument along with folklore suggests it was built for the mystical character Maeve, The Iron Age Queen of Connacht.

One of the primary causes of erosion to the monument is the habit of visitors to use cairn stones to form names or patterns on the ground around the cairn. Not only is it illegal to remove stones from this or any other monument, it is also considered to be a source of bad luck!"

If I everagain go across the sea to Ireland, I want to see that site. But I will not touch a stone upon a stone. You don't want to get on the bad side of Queen Maeve, oh no.