1974- Philippe Petit, who snuck into the World Trade Center with a 450 lb box of 3/4 inch cable the night before and took it to the 104th floor in a cargo elevator, schlepped the box up six flights to the roof (a friend helped).
In the early hours of the morning he strung the cable between the two towers.
Shortly after 7:00 he walked out on the rope. For 45 minutes he walked back and forth 7 to 8 times, kneeled, bowed, danced and even lied down on the cable before surrendering to the Port Authority Police.
All charges were later dropped and he was given a free pass to the observation deck of the WTC for life. (He last visited early September of 2001.)
Philippe, who was 6 days shy of his 25th birthday spent 6 years planning and practicing for this stunt.