Art Through Time: A Global View looks like a pretty amazing site from WNET. This is how the multimedia site describes itself:
Art Through Time: A Global View examines themes connecting works of art created around the world in different eras. The thirteen-part series explores diverse cultural perspectives on shared human experiences.
It would definitely be challenging to English Language Learners, but the site looks so good I’m still going to add it to The Best Sites For Learning About The World’s Different Cultures.