For me, the most adventurous thing i have done is way back my home burned down....and it made me put on a back pack and start walking all around the US on my own two feet....I took off from Florida and ended up on the other side of the US for a while then walked back later....it really was a longer story then that but thats it in a nutshell XD.
Falling asleep on mountain tops, starring at the stars, walking along railroad tracks for miles and miles, seeing sights out in the Colorado mountains that people normally never see, meeting people from all sides of life and much more ^.^ was a really memorable time of my life....I loved and miss every bit of it.