O.A.R. at Hollywood Casino Amphitheatre in Tinley Park 30 Jun, 2017 John Kosiewicz Alternative, Gallery, Indie, Rock On June 30, 2017, O.A.R. (also know as, Of a Revolution) performed at Hollywood Casino Amphitheatre in Tinley Park with picture perfect weather for the evening. Currently, O.A.R. is on tour with Train for …