In this camping tip, we show you how to freeze bottles of water to keep your cooler colder and cleaner - longer. It's simple, just freeze a few small to medium sized bottles of water in the freezer before your camping trip. Next, pack up your cooler using the frozen bottles rather than ice. You'll be able to pack the frozen bottles around your cooler contents. When the ice does eventually melt, you're left with fresh, cold drinking water.