I've never had a problem asking on departure at Den for a full bottle to take with me, unless they are out. I have that sucker drunk by the time I get to the rental car. Then I stop and by two large Evians at the shop/gas station before getting on the highway and have one of those drunk by the time I get to my destination, with the other to follow shortwith. That's how I've curbed altitude sickness. Water water water. <smile>