U.S. News Insider Tip: A normal ticket includes the Colosseum, Roman Forum and Palatine Hill (valid for 24 hours) and you can visit all three in one day. It doesn't include a visit to the ...

The epicenter of Roman Catholicism, St. Peter's Basilica is centered in Vatican City and is renowned for its stunning architecture. What's more, it's open daily for free. (Though it's closed on ...