Continuity mistake: Indians are on a hilltop and a jet vapour trail can be seen in the sky.
Continuity mistake: In the scene at The Yellow River where the Indians are chasing Gregory Peck and the gang of Omar Sharif on their way to the draft, you can see the same sequence with some trees (filmed with the camera holding up) twice within a second. (01:26:15)
Continuity mistake: In the final scene, after escaping the earthquake, you can see Camilla Sparv jumping across a gap with her horse shortly followed by Gregory Peck. You can see the clouds changing very fast within a split second. (01:57:30)
Other mistake: When Gregory Peck was being zoomed in on there are several fresh horse tracks.
Continuity mistake: When Gregory Peck and Camilla Sparv are climbing the rock ladder at "Cañón Del Oro", you can see that they are climbing the same piece of ladder over and over again. They do it 3 times. (01:48:45)
Answer: Have to say, I have not seen movie, but to answer your question, one of the earliest surviving depictions of a person wearing sunglasses is of the scientist Antoine Lavoisier in 1772.
Triviani