My favorite types of painting are Impressionist, Post-impressionist, Modern, and Contemporary. That's what I usually focus on when I visit museums.
However, this time I visited the National Gallery of Art in Washington DC a week ago Sunday, I started with looking at the older art. One of the many knockout pieces was Raphael's 1510 painting called The Alba Madonna. Not only is it beautiful and colorful, it is round! Here's the image from the website of the National Gallery which shows it without its frame, and also the photo I took which shows it in a very beautiful gold round frame. By the way, the colors did look bright as in my photo.
You can view some of my 3-D paintings on my website at www.jayrolfe.com/.