Those couple bottles of Perrier you thought would be plenty for a two-hour ride go surprisingly quick when your adventure turns into an ADVENTURE! and you find out your friends only brought one bottle. I like to fill my Kriega 3-liter Hydro pack with ice at the convenience store when I fill up with gas in the morning, and still be enjoying cold sips of water in the afternoon.

Staying hydrated makes a tremendous difference in maintaining your endurance. Food is good too, like trail mix or whatever, but water is essential. A first-aid kit should be in your bags too.