Actually, I saw hamadryas baboons to be exact.
The hamadryas, or sacred baboon, is one of five species of baboons in the world. It is a cliff-dwelling baboon, living at elevations of up to 1500 meters. It is usually found in northeast Africa, but can also be found in the Red Sea Hills in the southwestern Arabian Peninsula (where I saw them).
Baboons are opportunistic eaters, and there is plenty of opportunity along the road between Jeddah/Mecca and Ta'if in the Al-Sarawat Mountains. Drivers stop at just about every pull-off area to feed the baboons fruit, bread, and even juice boxes!
Below is a video compilation of them. I think they are so cool!