A visit to St Peter's Basilica is free, but you should expect long queues of two hours. Recommended: The most comfortable way to visit the basilica is with a guided tour.
Knee-Length Attire: Shorts, skirts, and dresses should at least reach the knee. It's advisable to avoid very short skirts or shorts. No Hats Inside: Just as in many other religious sites, it's respectful to remove your hat when entering the Pantheon.