The forecast promised sunshine. The forecast was made before you left the car park, and by two o'clock the cloud has come in from the west, the wind has picked up, and the path you were following has turned into a greasy ribbon of wet rock. Every fell walker learns this lesson eventually, usually on a summit, in the rain, wishing they had packed the thing that weighs almost nothing and matters more than anything else.

Start With the Map, and a Compass You Can Actually Use

A waterproof map at 1:25,000 scale is the single most useful item in your pack. It shows the walls, the streams, the crags and the contour detail that tells you whether that slope in front of you is a gentle ramp or something you would rather walk around. Keep it accessible, in a clear case clipped to your jacket or trouser pocket, not folded into the depths of your rucksack where you would need to take your gloves off to find it.

Pair it with a baseplate compass and, crucially, the skill to use the two together. A compass you have never practised with is a heavy piece of decoration.

• Set the map to north before you leave the car park, not when you are already unsure.
• Learn a rough timing rule: about four kilometres an hour on flat ground, plus a minute for every ten metres of ascent on a decent path.
• Use handrails such as walls, fences and streams as safety lines to follow.
• Deliberately aim off to one side of your target so you know which way to turn when you reach the feature.

A phone with an offline map is a sensible backup, kept in a waterproof pouch and charged. It is a backup, never the plan.

Layers, Spares and the Art of Not Getting Cold

Cotton is the enemy of a comfortable day on the hills. It soaks up sweat, holds it against your skin and chills you the moment you stop moving. Think in three parts instead: a base layer that moves moisture away, a mid layer that traps warmth, and a shell that keeps the wind and rain out.

• A genuinely waterproof jacket and trousers with taped seams, not merely showerproof ones.
• One spare warm layer, synthetic or wool, kept dry in a bag.
• Spare gloves and a hat, two pairs in winter.
• Gaiters for boggy ground, deep heather and snow.

Boots with real tread and a bit of ankle support will do more for your day than any gadget. Wear them in before you take them up a mountain.

The Emergency Shelter That Lives at the Bottom of the Bag

A lightweight bothy bag or group shelter weighs a few hundred grams and gets used far more often than people expect, and rarely for a genuine emergency. It cuts the wind instantly, traps a surprising amount of warmth and gives a cold or injured person somewhere to sit while you work out what to do next. Put it up once on a dry, calm day so you are not learning how it works in a gale.

Alongside it, carry a foam sit mat, a survival bag, a whistle on your rucksack strap where you can reach it with your teeth if your hands are busy, and a headtorch with fresh batteries plus a spare set. Darkness arrives quickly in the hills, and a torch that dies halfway down a rocky descent turns a long day into a dangerous one.

Food, Water and a Flask of Something Hot

Eat before you are hungry and drink before you are thirsty. Cold, wet and tired bodies burn through energy far faster than a warm one sitting indoors.

• A flask of hot drink or soup in cold weather, which lifts morale as much as it raises body temperature.
• High energy food you actually enjoy eating in the rain, such as oatcakes, nuts, flapjack and sandwiches.
• One to two litres of water, more in summer and on longer routes.
• A small first aid kit with blister plasters, tape and a tick tool, plus any personal medication.

A foil blanket tucked in a pocket costs almost nothing and has saved more than a few lives.

Wild Swimming Kit for Tarns and Pools

A dip in a high tarn or a river pool is one of the great pleasures of the British hills, and the water will be colder than you expect: often under fifteen degrees in summer, and in single figures in a deep corrie tarn all year round.

• A brightly coloured tow float, which makes you visible and gives you something to rest on.
• Neoprene socks or boots, gloves and a swim cap for anything longer than a quick plunge.
• A wetsuit or swimrun suit for extended swims, and a dry bag for everything else.
• A large changing robe or towel and warm layers waiting on the bank.

Enter gradually and breathe through the cold shock rather than diving in. Never swim alone, avoid weirs and fast-flowing water, check for blue-green algae, and remember that you will keep cooling down after you get out.

Skills, Signals and Knowing When to Turn Back

The best kit is a set of habits. Leave your route and expected return time with someone at home, carry a small card with your emergency contacts and any medical details, and know that six short blasts on a whistle, repeated at intervals, is the international signal for help.

Learn to read the sky and the ground: a cap of cloud on the summit, a sudden drop in wind, or a path that is wetter and steeper than expected are all useful information. Turning back is not failure. The hill will still be there next weekend, and the flask of tea at the car will taste better for it.