Hydration

With a bottle, you can keep track of how much you have drunk and it is easier to fill; from a reservoir, you drink while walking, so you drink more often — and on a long trail, this is more important than it sounds. In winter, the tube has a disadvantage: it freezes if you do not blow the water back after drinking. Where you do not have a reliable source of drinking water, sort out water treatment: a filter, chemicals or boiling. Do not automatically assume water from streams and lakes is clean, even high in the mountains; there might be a pasture above you.