Going to Rome for a City break in mid-September with a friend. Please advise how to plan - want to see most of the famous landmarks - Vatican, Colosseum, etc. I have checked Skip the line ticket to the Vatican Museums & the Sistine Chapel on Viator - all sold out. Are there any other websites I could book/reserve the tickets? Will we be able to queue on the day to enter? Any other landmarks/museums I might want to pre-book tickets? Shuttle from and to airport has been booked. TIA