Two bottle in cages, one in my back pocket. Hot days all 3 will be done by the time I get to the shack, but a moderate day I'll go through about 1 1/2 bottles. There is a drinking fountain at the base of the mountain, near the horse corral, and more at the Mt Baldy Village, but nothing in between. As long it's not in the high 80's or hotter, 3 bottles should be more then enough.