The ground here is older and more fragile than it looks

When you're deep in the hills, several hours from the nearest road, the idea that a single toilet stop could matter feels faintly absurd. But upland Britain is a slow landscape. Peat accumulates at roughly a millimetre a year. A tarn that looks like a puddle on the map may be the only reliable water source for miles, feeding burns that run down to farms, villages and reservoirs. What you leave behind doesn't vanish; it sits there, gets rained on, and slowly works its way into the system.

Most of us who camp, walk and overnight in bothies want the same thing: to arrive at a place that feels untouched. That doesn't happen by accident. It happens because the people before you made a small, deliberate effort. Here's how to do the same, in practical terms.

Digging a proper cathole

A cathole is simply a small hole dug to bury human waste, and done well it's fast, discreet and hygienic. Done badly, it's a smear of toilet paper and a health hazard beside the path. The difference comes down to a few specifics.

• Depth matters most. Aim for 15–20cm. Shallower than that and animals dig it up; deeper and you're into soil that is too cold and airless for the bacteria that break waste down. Fifteen centimetres is roughly the length of a trowel blade.
• Distance from water is non-negotiable. Stay at least 30 metres from any burn, tarn, spring or seep, and further on steep ground where runoff moves quickly. If you can reach the water in a few strides, you're too close.
• Keep away from paths, bothies and pitches. Fifty metres from a right of way and from any bothy or popular camping spot is a sensible minimum. Nobody wants to find your hole while pitching a tent.
• Choose dark, crumbly soil, not peat. This is the big one in Britain. Peat is acidic, waterlogged and largely anaerobic, so buried waste barely decomposes. It can sit there for years and then be uncovered by erosion. If the only ground available is deep peat, don't dig — treat it as a pack-out situation.
• Lift the turf, replace it. Cut a neat square of turf, set it aside, dig your hole, refill and press the turf back down. Scatter a few leaves or a little soil over the top so it doesn't read as a fresh scar.

Carry a proper trowel — a plastic or alloy one weighs almost nothing. Tent pegs, boot heels and sticks turn a two-minute job into twenty, and people give up. Toilet paper goes into your bag, always. It does not decompose at the rate you'd like, and buried paper is the single most common thing to reappear after rain or a digging fox.

When digging isn't possible

Rocky summits, gravel, saturated bog, frozen ground and deep snow all rule out a cathole. So do heavily used spots where the soil is already riddled with half-buried paper. In these places, and honestly as a default in busy areas, pack it out.

The kit is simple: a couple of strong, sealable bags, ideally one inside the other, plus a small pouch to carry them in. Dedicated waste bags with a gelling agent work well; ordinary dog poo bags are perfectly adequate if doubled and sealed. Add a small bottle of hand sanitiser and a bit of spare paper, and you have a system that weighs less than a flask.

Wet wipes, sanitary products, tampons and applicators never go in a hole or down a bothy toilet. Carry them out in the same bag. If you use a menstrual cup, rinse it with water carried away from the source and empty the water into your waste bag, not into the burn.

Bothies: shared shelter, shared responsibility

Most bothies have no toilet, and the ones that do are maintained by volunteers and emptied rarely. A few rules keep them habitable.

• Use the toilet if there is one, even if it's a composting or chemical setup that looks unloved. It exists because the alternative was worse.
• If there's a spade or trowel kept in the bothy, use it and put it back where you found it.
• Never use the area immediately behind or beside the building. It's the first ground to be churned up and the last place anyone wants to walk.
• Don't burn waste in the stove. It smells, it doesn't fully combust, and the next person has to deal with the result.
• If the ground around a popular bothy is already a mess, don't add to it — walk a few hundred metres further, or pack out.

Treat the bothy as a house you're borrowing, because that's exactly what it is.

Tarns, burns and the water you drink

Upland tarns are often small, shallow and slow to flush. That means anything entering the water stays in it, feeding algal growth and, in high-use areas, raising the risk of contamination for everyone downstream — including you, if you're filtering or boiling from that burn later.

So keep all washing, teeth cleaning and dishwashing at least 30 metres back from the water's edge, and use as little soap as possible; even biodegradable soap needs soil to break it down properly and shouldn't go straight into a tarn. Empty toothpaste spit into a hole, not onto the shore. And if you're wild swimming, use the facilities before you leave the car park, not afterwards behind a boulder.

Small habits, permanent difference

The most effective thing you can do is plan ahead. Use the toilets at the car park or the village before you set off. Know roughly where your day's water stops are, and time your stops accordingly. Carry a trowel and a waste bag on every trip, even a short one, so the decision is already made when the moment arrives.

None of this is difficult, and none of it takes long. It just requires you to see the place as it will be in ten years, when someone else stands where you're standing now. Do that, and the hills keep giving you exactly what you came for.