Just think of all of the amazing things you have been a witness to throughout history. Now, think of all of the things other people you know have seen. It's a lot of ground to cover, when it comes to memories. But then, if you want to realize just how small you are in the grand scheme of things, think of all of the awesome events throughout history you haven't seen, didn't know about and probably wouldn't have known about... until now. These historic photo opportunities happened in the blink of an eye, but someone was lucky enough to capture it on film. They are the kind of events you can't quite believe happened (but you're so glad you have evidence of it). The strangest celebrities knew each other...
1. William Harley and Arthur Davidson (1914).
2. Muhammad Ali and Michael Jordan (1992).
3. The Beatles before their iconic Abbey Road shot.
4. The first car factory in the United States for Ford (1926).
5. Robin Williams joining the cheerleading squad (1980).
6. Boxing in Yankee stadium (1923).
7. Marilyn Monroe and Sammy Davis, Jr.
8. Einstein and his furry shoes.
9. The last picture of the Titanic before sinking (1912).
10. Three kids and their spooky "Halloween people" costumes (1900).
11. Camp Nou Stadium in Barcelona (1925).
12. The streets of Chicago (1967).
13. Bill Gates's mugshot for driving without a license (1977).
14. Osama Bin Laden and his judo classmates.
15. A child with artificial legs (1898).
16. Diane Keaton and Al Pacino on The Godfather set (1972).
17. Jimi Hendrix and Mick Jagger (1969).
18. Arnold Schwarzenegger seeing NYC for the first time (1968).
19. Bruce Lee on the dance floor.
20. The making of Batman (1966).
21. The beloved Hachiko before his burial.
22. The Beatles and Muhammad Ali (1964).
23. German children play with stacks of money during the hyperinflation period of the Weimar Republic, 1922.
24. Nazi celebration in Buckeberg in 1934.
25. MLK Jr. and Marlon Brando.
26. Nazis singing to encourage people to follow their boycott of Jewish shops in 1933.
27. Charlie Chaplin and Albert Einstein.
28. A Jewish woman in Austria in 1938 sitting on a bench marked "Only for Jews."
29. Nazi SS troops lounging outside of the Olympic Games in Berlin in 1936.
30. SS troops taking a loyalty oath in Munich, 1938.
31. Applause and salutes for Hitler after Germany successfully annexed Austria in 1938.
32. Another angle, and in color.
33. A frozen Soviet fighter propped up by Finnish soldiers to wreak psychological warfare on the invading Soviets.
34. Joseph Stalin's record from the Tsarist Secret Police in 1911.
35. Chuck Norris and Bruce Lee.
36. Joseph Stalin (right), and his body double Felix Dadaev (left).
37. Stalin's son Yakov Dzhugashvili captured by the Germans in 1941. He was later killed in a prison camp.
38. A German soldier share some of his food with a local Russian mother.
39. A Frenchman cries during the Nazi occupation in 1940.
40. Steve Jobs and Bill Gates.
41. Japanese Special Naval Landing Forces during the battle of Shanghai, 1937.
42. About to be executed by the Finns, this Russian spy laughs.