Back in the old days when mountain bikes weren’t such the distant cousins of road bikes that they are today, most people would use water bottles held in place in flimsy bottle cages, borrowed from road cycling. But you would lose ‘em on rocky descents, the nozzle gets covered in dog crap and they only hold up to 750ml of fluid, which isn’t very much.

Then somebody clever along the way struck on the idea of designing a ‘bladder’ to hold a couple of litres of water (or whatever your preferred choice of drink is) that could live inside a rucksack and a hose and nozzle would make drinking on the move, without stopping, a possibility. The rest, as they say, is history, as the hydration pack has become synonymous with mountain biking.

Not only is a hydration pack the best way of staying hydrated but it allows you to keep you hands right where they should be – on the bars! Drinking on the move means you never have to stop or fumble around for a bottle, meaning you get more time to think about which line to take next.

Hydration packs are not only a fashion accessory that hold bags of water, quite literally too, but they also double up as a great luggage system for spares, jackets and even a spade, if digging down at the jump spot is your thing.

These days riders from full on XC whippets to hardcore freeriders carry some form of hydration system on their backs, and there are packs that range from minimalist affairs with not enough space for a spare tube to those cavernous packs intended for multi-day epics.

If you’re buying your first hydration pack, here’s some very useful info to know before you make a purchase over the next three pages (click the arrow down below to go to the next page).