Anyone who hikes, camps or travels off the beaten track eventually hits the same problem: you're thirsty, the nearest water looks dubious, and there's nothing between you and a bad few days. The fix, according to outdoor writers at Explore, is surprisingly simple — swap your regular bottle for one with built-in filtration or purification.

Filtered bottles work a bit like pool pump filters, using a replaceable cartridge to catch protozoa, bacteria and debris as you drink. A popular example is the Katadyn BeFree 1L, a lightweight soft-sided bottle where the filter sits in the removable cap. You fill it from a stream or tap, drink normally, and clean the filter by swishing clean water through it. Because the bottle is flexible, it rolls or flattens down when empty — a genuine plus when pack space is tight.

Purifying bottles go a step further. Filters catch the bigger nasties, but viruses like norovirus and hepatitis A are small enough to slip through, so purifiers use chemicals or UV light to kill them. That extra layer matters in places where tap water is genuinely unsafe, which makes these bottles as useful for city travellers in regions with contaminated water as they are for backcountry campers.

Two purifying options stand out. The UVBrite Beam+ pairs a filter with a UV-C sterilisation system that zaps viruses and bacteria, and it runs a self-cleaning cycle every six hours. It's listed on Amazon for $49.99. The GRAYL GeoPress Purifier takes a more hands-on approach: fill the outer casing from any water source, press the inner container down, and in about 10 seconds you have drinkable water. Its cartridge filters and purifies at once, stripping out viruses, bacteria, protozoa, chemicals and microplastics.

Why should this be on your packing list? Because clean water is the one thing you can't improvise. Staying hydrated is what keeps you warm in winter and sharp on long treks, and relying on bottled water means either carrying kilos of plastic or adding single-use waste to every trip. A filter or purifier bottle lets you refill from taps, streams and hotel sinks almost anywhere, cutting cost and plastic while removing the guesswork about what's actually in your water. For hikers, campers, van-lifers and long-haul travellers alike, it's the rare gadget that earns its spot on every single trip.

Story sourced from Explore.