Possibly. His first "Sinbad" film in 1958 had one moving skeleton for the hero to fight; this one has a whole platoon of them, each part painstakingly moved one tiny distance at a time personally by Harryhausen through stop-motion techniques. The seven-headed Hydra is another technical marvel. There are some other nifty creatures for Jason and his crew to battle, but for me, the most impressive of them all turns up first: the gigantic Talos, the Man of Bronze.
I was a kid when this came out, and I don't think I'll ever forget that moment when the huge, crouched statue came to life, turned his head towards the two men below him (his bronze head screeching with the tear of metal), climbed off of his pedestal, and proceeded to chase Jason and his men. Talos was giant like Godzilla, but as single-minded as the Terminator: all he wants to do is track Jason's crew down until he kills them all. This gave me nightmares. Bernard Herrmann's score is one of his best, making music to match Harryhausen's images. (Herrmann was coming off of other Harryhausen's, plus Hitchcock's "Vertigo," "North by Northwest" and "Psycho," and knew how to thrill you.)
Tom Hanks, who was also a kid when this came out, has said: "Everybody thinks that 'Citizen Kane' was the greatest movie ever made. But if you were young in 1963, you know the real answer is: 'Jason and the Argonauts.'"
