Fodor's Expert Review Santa Maria in Cosmedin

One of Rome's oldest churches—built in the 6th century and restored in the late 19th century—is on the Piazza della Bocca della Verità, originally the location of the Forum Boarium, ancient Rome's cattle market and later the site of public executions. Although the church has a haunting interior and contains the flower-crowned skull of St. Valentine, who is celebrated every February 14th, it plays second fiddle to the renowned artifact installed out in its portico.

The Bocca della Verità (Mouth of Truth) is in reality nothing more than an ancient drain cover, unearthed during the Middle Ages. Legend has it, however, that the teeth will clamp down on a liar's hand if they dare to tell a fib while holding their fingers up to the fearsome mouth. Hordes of tourists line up to take the test every day (kids especially get a kick out of it).