All invited to Music in the Arb, a series of free summer concerts at the amphitheater in Nichols Arboretum. Featuring eclectic music from locally and nationally known bands and performers. Tonight’s performance by Cairn to Cairn, playing Irish/Celtic acoustic music that combines traditional songs with contemporary instrumentals and vocals. Visit our website at mbgna.umich.edu or call 734-647-7600 for more information and directions. Concert is free and begins at 6 pm.