What to Eat on a Munro: Food and Hydration for the Hills

It is the part of mountain preparation people most often get wrong. A long Munro day can burn somewhere between 3,000 and 5,000 calories, yet walkers routinely set off with a single sandwich and run out of energy halfway up. Food and water are not luxuries on the hill — they are equipment, every bit as important as your waterproofs. Fuel properly and the climb feels manageable; neglect it and you "bonk", that sudden, leg-emptying wall of fatigue, often at the worst possible moment.

Before you start: the night before and the morning of

Good fuelling begins before you reach the car park. Eat a proper meal the evening before a big day — carbohydrate-rich food tops up the energy stores your muscles will draw on — and have a solid breakfast on the morning itself. Porridge is the hillwalker's classic for good reason: it releases its energy slowly and keeps you going well into the morning rather than spiking and crashing.

On the hill: graze, don't gorge

The key principle on the move is to eat little and often rather than waiting for one big lunch stop. Your body absorbs a steady trickle of food far better than an occasional feast, and grazing every hour keeps your energy level steady and your concentration sharp. The old advice holds: eat before you are hungry, because by the time you feel genuinely hungry your tank is already running low.

Aim for a mix of:

• Quick-release carbohydrate for instant energy — flapjack, dried fruit, jelly sweets, a banana.
• Slow-release food to sustain you — sandwiches, oatcakes, nuts, a proper roll.
• Something you actually want to eat. On a cold, wet summit, appetite vanishes, so carry food you will look forward to. Many walkers swear by chocolate and a flask of something hot for exactly this reason.

Always pack more than you plan to eat. An emergency ration — a chocolate bar or energy gel kept untouched at the bottom of the pack — costs almost nothing to carry and can make a real difference if the day runs long or something goes wrong.

Hydration: more than you think

Dehydration creeps up quietly and saps both strength and judgement long before you feel thirsty. As a rough guide, carry at least one to two litres for a typical Munro day, and more in hot weather or on a long round. Scotland's great advantage is its abundant hill water — many walkers refill from fast-flowing burns high on the mountain, well above any habitation or grazing, which lets you carry less. Use judgement about the source, and carry a means of purification if you are unsure. In cold weather a warm drink in a flask does as much for morale as for hydration.

Tailor it to the day

A short summer hill needs far less than a long winter round or a remote multi-day trip into Knoydart. Scale your food and water to the length and seriousness of the outing, and remember that cold weather and hard effort both increase how much you need. Get the fuelling right and you will feel the difference on every climb — fewer flat patches, a stronger summit and a safer descent. Once you are back down, log the hill in the Munros app and start planning the next one.

Related guides

• Complete Munro bagging packing list — where food fits in the pack
• Munro bagging fitness and training — the engine the fuel feeds
• Mountain first aid essentials — for when a day goes wrong