I have got to mention tony,s top tips rule 104 many a time in the mountans and no water . you won’t bleave how much water you can use up hill climbing .Once walking the Corrieyairack Pass 27 mile on a boiling hot day we where assuming we would find water on route, all the burns were dry or full of red alge, at around 2000 feet one pal got heat stroke and I used up the last of my water cooling him down and still only 2 or 3 hours in to the walk, unless its pissing down Don’t rely on finding water in the hills.