I've mentioned this elsewhere, but think it bears repeating for this film's fans.

Someone who has viewed the new Warner Archive MOD states that the letterboxing restores a long-missing detail from the film's full frame transfers (VHS, laserdisc, TCM). When the slave dangling from a rope over a chasm falls to his death, we only hear his scream in full frame, then see his crumpled body below.

In the widescreen version, we see cartoon imagery that actually depicts the slave falling to his death, on the extreme leff of the picture. I haven't seen the film in a theater since 1972, so I had totally forgotten about that detail. It will be interesting to see it again after so long.