Kids love their parents, but come to think of them as old and out of touch. Eventually all of us realize that our parents were once young, and have a lifetime of experience that they might never have told us about. Leo_nardo has a picture of his mom casually strolling through a line of armed National Guard troops at a 1969 protest in Berkeley. While pregnant. She met the photographer at an exhibit weeks later and got a copy of the picture. ThomCarn showed us his dad at age 22, when he flew a Mirage F-1 for the French Air Force.
Some were warriors or brave immigrants, others took to the road for adventure. One even pinned Chuck Norris. Some just looked too cool for the next generation to believe. See 76 such pictures in a ranked list at Bored Panda.