MUST SEE historic buildings and masterpieces. That said, Rome definitely has masterpieces that will feed your soul if you allow yourself to spend quality time with them.
On top of all the Must See Lists is the Sistine Chapel and its ceiling by Michelangelo. The Sistine Chapel gets over 10,000 visitors everyday. It takes 12 full time museum guards to manage the crowd flow, and to remind these people that the Sistine Chapel is a house of worship, so be respectful, be quite, don't talk on your cell phones, or take photos. (I would absolutely hate to have that job)
You enter the chapel by a small nondescript side door. The first impression is seeing a mass of people all looking up. Then your eyes move upward and there it is... and then you stumble off the stairs that you didn't notice because you were looking up.
I could go on and on about the impact of seeing this masterpiece, but there is already plenty of that on the internet. So, I am skipping to later that day, around 4:30, when we went back for a highly recommended second look. There was only 15 people in the chapel!!! There was actually setting available! We hung out for about an hour and a half, soaking up as much as possible. Quietly pointing out the beautiful details to each other.
One question did come up, What exactly were Adam and Eve doing just before the snake in the tree interrupted them?