Staircase To The Top of Saint Peters Basilica in Vatican City

I Just went on a tour at Saint Peters Basilica in the Vatican City in Rome. I bought a ticket to go on the roof. I rode an elevator to the rooftop then went up some stairs to reach to top of the dome. The stairs are sometimes around a pole sometimes straight and some are curved. At one point it was very narrow. You can see this in the video. There was so much to see, the experience was amazing.