Your Feet at 5,895m

Altitude sickness dominates every Kilimanjaro conversation. But foot damage — blisters, crushed toenails, swelling that makes boots unwearable — quietly ends more summit attempts than any altitude symptom. Unlike altitude illness, foot pain does not improve with rest or medication. The only treatment is descent — and once you descend far enough to relieve the pressure, you have lost your acclimatisation window.

Three Terrain Zones — Three Different Foot Threats

Blister Prevention: Sock System and Taping Protocol

The most effective prevention is a two-layer sock system. A thin, seamless liner sock sits against your skin; a thick merino wool outer sock sits over it. The liner reduces friction. The outer absorbs impact and moves with your boot. Cotton retains moisture and dramatically increases blister risk — every sock you wear on Kilimanjaro should be synthetic or wool.

Taping protocol: Each morning before starting, run your thumb along the sole, heel, and between toes. Any warm or raised area gets a layer of moleskin or medical tape applied smoothly with no wrinkles. Change tape every evening — bunched tape creates as much friction as no tape.

When to pop: Small blisters under 1cm with intact skin should be left alone. Larger blisters that prevent comfortable walking can be drained by a guide using a sterile needle — fluid pressed out gently without peeling skin, then antiseptic and a donut-shaped molefoam pad. Never tear skin away from a blister.

Toenail Blackening: Prevention and Recovery

Black toenails are caused by repeated subungual haemorrhaging — tiny blood vessels under the nail rupturing from sustained downhill pressure. The main culprit: boots slightly too tight at the toe, or heel-lock technique forcing the foot forward on each step.

Prevention: Size boots half a size larger than street size with the thick hiking socks you will actually wear. Use a heel-lock lace technique — thread the lace under itself at the ankle eyelet and pull tight before tying. Wear stiff sole plates on descent-heavy days. Tape thin foam pads directly over each toenail before starting each day's descent.

Recovery: A blackened toenail is almost never a medical emergency. It will likely fall off over 4-8 weeks post-climb — normal. Keep it clean, apply antiseptic, protect the exposed nail bed with a sterile dressing. Full new nail takes 3-4 months.

Foot Swelling: Normal vs. Altitude Edema

Mild bilateral swelling is a normal altitude response affecting most climbers above 4,000 metres. It is caused by fluid redistribution as the body adapts to reduced oxygen. Both feet swell roughly equally. Remove boots at every opportunity above 4,000m, elevate feet during lunch stops, and maintain consistent hydration.

When to be concerned: Significant asymmetric swelling — one foot notably larger than the other — alongside coughing, confusion, or poor coordination may indicate altitude edema. Report this to your guide immediately. This is a medical emergency requiring descent.

Boot Break-In: 150km Minimum

New boots must accumulate at least 150 kilometres of wear before Kilimanjaro. There is no shortcut. Break in across varied terrain — paved surfaces do not flex boots the way trail does. Complete two full-day hikes with an 8-10kg loaded pack before you travel. Any pressure point felt during break-in will be a blister by day three on Kili. If you feel it, resolve it with stretching or a visit to a boot-fitter before departure.