When doing outdoor sports like hiking or biking I'll always take a lot of cold water with me. I love to drink cold water and I feel more refreshed compared to drinking warm or not-so-cold water. But when the weather is really hot, I have a problem. I can't keep the water cool the whole day. I tried various techniques like trying to isolate the bottles in towels or dedicated water coolers that you can buy in supermarkets. But nothing worked for...
Originally asked by RoflcoptrException on Stack Exchange (outdoors) (CC BY-SA 3.0).
