Vatican Museums and Sistine Chapel Tickets Reservations (part 1 of 4). Your Choice: TICKETS FOR COORDINATED GROUP (NO GUIDED TOUR). IMPORTANT NOTICE: pre-booked tickets allow to enter the Museums without waiting in line. It is necessary to book at least. . As the Museums are very crowded and available places are limited, we suggest you to book tickets well in advance. OPENING DAYS. The Vatican Museums are closed on Sunday, except for the last Sunday of the month (no guided tours are available on this day).