Pack an outfit that meets the requirements comfortably for a whole day of walking, since the museum route alone is 2–3 hours. A hot forecast does not remove a sacred site’s dress expectations.
Vatican City · YOUR QUESTION, ANSWERED
What should I wear at the Vatican?
Cover your shoulders and knees. St. Peter’s requires shoulders covered, no shorts above the knee, no miniskirts, and no hats inside; the rule applies to men and women and is checked at the security line. The Vatican Museums, including the Sistine Chapel, apply the same shoulders-and-knees standard under their own visitor rules. Visitors who do not comply are turned away.
Sources & further readingSt. Peter's Basilica: visitor questionsVatican Museums: visitor information
Official sources cover institutional information. Suggested pacing and itinerary choices are planning guidance. Check current arrangements for your travel dates.