I'm going to watch it tommorow morning quite early as I heard it was 4 hours, is that true?
Yes, the long unedited version ( which is the the only version to watch btw ) is about 3 hours and 45 minutes long. But it goes very fast.
Don Cardi
The version that Sergio Leone wanted us to see was a 6 hour version, what i would give to see that version. It might be comparable to The Godfather Part II, The Godfather 1 was just flawless and better than Once Upon A Time In America for sure.