The spires of the Cathedral of Milan in Milan, Italy, are among the sites encountered during a trek through Mark Twain's "The Innocents Abroad." | AP

The Palace of the Doges in Venice, Italy. | AP

Gondolas jockey for position on the Grande Canale in the heart of Venice, Italy. | AP

A visitor checks out the rooftop of the cathedral of Milan. | AP

The view from the Bridge of Sighs and the canals beyond it await visitors to Venice. | AP