Time.... Man really hasn't changed.
Historically educational and the sets were incredible! Easy enough to grasp what's happening. There are several time periods with each telling the beginning of its story and then intermission. Repeat until movie ends. It's a longer movie but one that glued me to it. I was in my 50's. I may not have appreciated it or as much in my younger years.
I happened by this movie channel surfing some 10+ yrs ago. Had to have it. Own it. Have watched twice since owning. 3 times I've viewed movie. It turned me on to the genre. Metropolis was next for me. It's also amazing.