Why carry a tarp instead of a tent?

A 3 x 3 m silnylon or polyester tarp weighs in the region of 500–700 g, and with eight pegs and a couple of 2 mm cord guylines you are still comfortably under a kilo. Compare that with a one-person tent offering similar protection and you have saved half a kilo or more — weight that can go into a warmer sleeping bag or an extra day of food.

The trade-off is that a tarp has no floor, no inner and no poles, so it depends on trees, trekking poles, bike handlebars or a few cut sticks to hold it up. What you get in return is flexibility. In a wood you can sling a lean-to between two trunks; on open fell you can pitch a full A-frame with poles. On a still, mild night you can roll one side right back and watch the stars; when the weather turns you can drop it low and batten everything down. That adaptability is why so many long-distance walkers end up carrying a tarp as a second shelter, or as their only one.

Choosing a pitch that works with the weather

Most tarps fail not because of bad knots but because of a bad spot. Prevailing winds in the UK come from the south-west, so look for ground with a natural backstop — a wall, a hedge, a bank, or the lee side of a stand of trees — and pitch your low, closed end into the weather.

Avoid the obvious flat ground at the bottom of a valley. Cold air pools there, which means heavy dew, mist and often a frost when the tops are clear. A slightly raised shelf or a gentle shoulder 20–30 m above the valley floor is usually drier and warmer. Stay well clear of watercourses, however small; a summer trickle can become a torrent after an hour of hill rain.

Look up before you look down. Dead branches and cracked limbs — known to many as widow-makers — are a genuine hazard in old woodland, and ash in particular has been shedding limbs widely. Never pitch beneath a lone mature tree in a thunderstorm, and think twice about anything leaning over your sleeping head.

• Ground: level enough to sleep on, with no roots or stones under your hip.
• Drainage: slight slope, or at least ground that is not a sponge.
• Wind: a backstop to windward and enough space to tension guylines.
• Wildlife: off deer paths, off ground-nesting bird habitat and away from livestock.

Knots worth knowing before you go

You can pitch a tarp with four knots and never need another. Learn them at home in the dry, with gloves on, until your hands know them better than your head does.

• Taut-line hitch — the adjustable guyline knot. It slides to tension and grips under load, which is exactly what you want when a line slackens in the wet.
• Bowline — a fixed loop that will not jam, ideal for the tarp's corner eyelets or for a peg you want to retrieve easily.
• Clove hitch — fast, adjustable, perfect for tying a ridgeline to a trekking pole or a tree.
• Two half hitches — a quick, reliable way to finish off a line around a peg or a trunk.

Add a prusik if you want an adjustable ridgeline you can tension from underneath without untying anything. Protect tree bark by using a wide strap or a doubled length of cord rather than thin line cutting into living wood.

Pitching: ridgelines and the A-frame

The classic is the A-frame. Run a ridgeline between two points at roughly 1.6–1.8 m, drape the tarp over it, and peg the long edges out at an angle of about 45 degrees to the vertical. That angle sheds rain well and gives you headroom in the middle. In calm weather leave the edges 30–40 cm off the ground for airflow; in wind bring them down to 15–20 cm.

Pegs should go in at roughly 45 degrees, leaning away from the direction of pull. On soft ground, pile a stone or a boot on top. Fit a short loop of shock cord between the guyline and the tarp where you can — it absorbs gusts so your pegs stay put instead of being wrenched out one by one at 3 a.m.

If the wind is really up, pitch a plough-point or a flying-V: one end closed and low into the wind, the other sloped and open. It is a cramped night, but you will still be there in the morning.

Staying dry when the rain arrives sideways

Water runs down the fabric and, without help, will travel along the underside of the tarp and drip onto you. Tie a short length of cord around the ridgeline with a loose knot and let it hang below the tarp — a drip line — to catch that flow and channel it clear of your sleeping area.

Pitch so the widest gap faces away from the wind, not into it, and resist the temptation to touch the inside of the fabric in heavy rain. Contact wicks water through, quickly. Take a groundsheet slightly smaller than your sleeping area — polycro or a lightweight footprint — so rain running off the edges does not land on your mat.

In Scotland especially, a tarp without a midge net can be miserable from May to September. A bivvy bag with a netted hood, or a head net hung from the ridgeline, transforms the experience.

Wildlife, leave no trace and the morning after

Keep food sealed and stored away from where you sleep; inquisitive foxes, mice and, in some areas, pine martens will find a dropped oatcake. Avoid camping on flower-rich grassland, bilberry or heather if there is a bare patch nearby, and give grazing livestock a wide berth, closing any gate you open.

Use a stove rather than a fire. If you do light one where it is permitted, burn only dead, fallen wood, keep it small and never on peat or in dry conditions. Shed ticks are worth a check before bed, and from March to July keep your distance from ground-nesting birds such as curlew, lapwing and skylark.

Finally, know the rules where you are. In Scotland, wild camping is covered by the right of responsible access — small numbers, short stays, leave nothing behind. In England and Wales, it generally requires the landowner's permission, with a few permissive exceptions. Pitch late, leave early, and the next walker will never know you were there.