How to Pack for the Andes Mountains

Pack in layers for extreme temperature swings, prioritize high-altitude gear like sunglasses and sunscreen, and bring both waterproof and insulating layers. Your pack weight matters more at altitude—every ounce counts when you're breathing thin air.

  1. Start with base layers. Pack 2-3 merino wool or synthetic base layer sets. Cotton kills in the Andes—it stays wet and loses insulation. Merino wool regulates temperature and resists odor for multi-day trips.
  2. Add insulating layers. Bring a down jacket rated to at least 20°F (-7°C) and a fleece or wool mid-layer. Down compresses small but loses warmth when wet, so pack it in a stuff sack with a dry bag.
  3. Pack waterproof outer shell. A breathable rain jacket and waterproof pants are non-negotiable. Weather changes fast at altitude. Look for 3-layer Gore-Tex or similar—2.5 layer shells work for day hikes but not multi-day treks.
  4. Protect against UV exposure. Pack SPF 50+ sunscreen, zinc stick for nose/lips, glacier glasses (category 4), and a wide-brimmed hat. UV exposure increases 10-12% per 1,000 feet of elevation. Snow and rock reflect 80% more UV than sea level.
  5. Choose appropriate footwear. Waterproof hiking boots with ankle support for trekking, plus camp shoes (lightweight sandals or slip-ons). Break in boots for 50+ miles before your trip. Bring gaiters to keep rocks and snow out.
  6. Pack altitude-specific items. Altitude sickness medication (consult your doctor), electrolyte tablets, and extra water capacity (4+ liters). Dehydration happens faster at altitude. Pack a headlamp with extra batteries—days are shorter near the equator.
Can I rent gear instead of buying?
Yes, major trekking hubs like Cusco, Huacachina, La Paz, and Quito have rental shops. Quality varies—inspect everything carefully. Expect to pay $15-25 per day for a full gear package. Buy your own base layers and socks for hygiene.
How much should my pack weigh?
Aim for 20-25% of your body weight maximum. At high altitude, every extra pound matters. A 150-pound person should carry no more than 30-37 pounds including water. Porters can carry gear on organized treks for $30-50 per day.
What's different about packing for the Amazon side versus Pacific side?
Amazon side (eastern slopes) gets more rain year-round—prioritize waterproof gear and quick-dry fabrics. Pacific side (western slopes) is drier but has bigger temperature swings—focus on insulating layers. Both sides need serious UV protection.
Do I need special sleeping gear?
Yes if camping. Sleeping bags rated to 10°F (-12°C) minimum, and a closed-cell foam pad plus inflatable pad for insulation from cold ground. Temperatures can drop 40°F from day to night even in summer.