Do I really need a money belt?

In crowded bus terminals or busy markets, yes. Use it for your passport and emergency debit card; keep daily spending money in your pocket.

Should I bring a sleeping bag?

Only if you plan to do multi-day trekking like the Salkantay or Huayhuash. Otherwise, hostels provide linens, and it just adds unnecessary bulk.

Is it better to carry a duffel or a backpack?

A backpack is essential. South American sidewalks are uneven, and you will frequently need to walk blocks to reach your hostel.

Essential Gear for Backpacking South America

Prioritize a high-quality 40-50 liter backpack, a versatile layering system for extreme altitude changes, and a robust water filtration system. Focus on modular organization and security to handle everything from Andean treks to humid tropical bus terminals.

Select the Right Pack. Choose a 40-50 liter backpack with a solid suspension system. Ensure it is front-loading rather than top-loading for easier access to gear in cramped hostels. Use a separate 15-20 liter daypack for hikes and daily exploring.
Master the Layering System. Pack a base layer (merino wool), a lightweight fleece mid-layer, and a high-quality down or synthetic puffy jacket. Add a lightweight, breathable rain shell to handle sudden mountain downpours.
Footwear Strategy. Bring one pair of broken-in trail runners for both trekking and city walking. Avoid heavy hiking boots unless you are doing multiple high-altitude technical climbs. Pack a pair of lightweight, quick-dry sandals for hostel showers.
Security and Organization. Use color-coded packing cubes to organize your bag. Carry a slash-proof daypack or a hidden money belt for your passport and emergency cash. Bring a sturdy cable lock to secure your bag to hostel bed frames.
Tech and Health. Bring a universal travel adapter with USB-C ports. Carry a 10,000mAh power bank for long bus rides. Pack a basic medical kit with electrolyte packets, Imodium, and blister treatment (Compeed).

Do I really need a money belt?: In crowded bus terminals or busy markets, yes. Use it for your passport and emergency debit card; keep daily spending money in your pocket.
Should I bring a sleeping bag?: Only if you plan to do multi-day trekking like the Salkantay or Huayhuash. Otherwise, hostels provide linens, and it just adds unnecessary bulk.
Is it better to carry a duffel or a backpack?: A backpack is essential. South American sidewalks are uneven, and you will frequently need to walk blocks to reach your hostel.