A traditional Irish group that dates back to the late 1980s, Dervish has been called "an icon of Irish music." The Sligo Borough Council's Decision awarded the band the Freedom of the Borough of Sligo, putting them in the same company as the Irish poet William Butler Yeats. The group performs tonight at 7:30 at the Cleveland Museum of Art's Gartner Auditorium. Tickets are $53 to $69, $48 to $62 for CMA members. (Niesel)