Second day. Vatican Museum or Musei Vaticani. No trick you can play here about ticket. MAKE SURE you reserve the ticket in advance, unless you join a tour group.
I took the second picture to show you the queue for entering. The first picture is the exit of the museum, on its left is the entrance. You may see a crowd there lining up for ticket and the line goes around the castle wall of Vatican city. I think the line is longer than 150m. This is the longest line I can see AT THE MOMENT (which means a even longer line is coming in later posts)
Oh, btw before we went to the Museum, we had a good breakfast at this shops, which is close to the Vatican.