Basilica di Santa Maria in Cosmedin

This guide to the Mouth of Truth at Santa Maria in Cosmedin in Rome opens with Gregory Peck's unscripted prank on Audrey Hepburn during the filming of Roman Holiday in 1953, the moment that put this ancient marble mask on every tourist's map. It traces the mask itself back roughly two thousand years, possibly to a drain cover from the nearby Temple of Hercules Victor, and to a superstition medieval Romans built around it long before Hollywood arrived. Look at the queue outside the porch — the legend still gathers a crowd.