21-Day South America Itinerary: Peru, Argentina, Brazil

You can fit the highlights of south america into a three‑week trip, but only if you plan the flights and visas tightly. This itinerary moves you from the Andes to the pampas to the coast, with concrete numbers on travel time and cost.

The 21‑Day South America Itinerary at a Glance

Day 1‑7: Cusco & Machu Picchu (Peru)

• Arrive in Cusco (altitude 3,400 m). Spend two nights acclimating before the train to Aguas Calientes.
• Take the early morning train (PeruRail or Inca Rail) to Machu Picchu; the round‑trip ticket costs $70‑$120 depending on class.
• Hike the Inca Trail (4‑day permit) only if you book 6 months ahead; otherwise, the train‑bus combo is the reliable option.
• When NOT to overland: Attempting a bus from Cusco to Buenos Aires will take 2 days of nonstop travel and cost $120‑$150, but you’ll lose a full day of sightseeing and risk altitude sickness on the road. Flying saves time and money.

Day 8‑14: Buenos Aires (Argentina)

• Book a direct LATAM flight from Cusco to Buenos Aires; the flight lands in the evening, giving you a full night to recover.
• Use the Subte (subway) to explore neighborhoods: Palermo for nightlife, San Telmo for markets, and La Boca for colorful streets.
• Visa note: Most nationalities need an e‑visa ($100) for Argentina; apply online 48 hours before departure.
• Best time to visit: March‑May (spring) offers mild weather and fewer tourists. Prices for mid‑range hotels drop 15‑20 % compared to peak summer.

Day 15‑21: Rio de Janeiro (Brazil)

• Fly Buenos Aires → Rio with Azul; the flight departs early morning and arrives before lunch.
• Stay in Copacabana or Ipanema for beach access; both areas have hostels starting at $25 per night.
• Purchase a combined ticket for Christ the Redeemer and Sugarloaf Mountain ($55) to save on separate entries.
• Visa requirement: Most travelers need an e‑visa ($30) for Brazil; the process takes 5‑7 business days.
• Best time to visit: March‑May (late summer) balances warm weather with lower hotel rates. Carnival rehearsals start in February, so if you’re there in early March you’ll catch the final parades.

Flight and Visa Summary

• Total flight time: 8 hours 15 minutes (Cusco → Buenos Aires → Rio).
• Total flight cost: $650‑$1,020 (economy, mid‑range airlines).
• Total visa fees: $130‑$150 (Argentina + Brazil).
• Overland alternative: None viable for the long leg; the only realistic overland option is a bus from Buenos Aires to Montevideo (5 hours, $30), which adds little value for a three‑week schedule.

Budget Snapshot (Per Person)

• Flights: $650‑$1,020
• Accommodation (21 nights, mixed hostels & 3‑star hotels): $420‑$630
• Activities & entrance fees: $180‑$250
• Food (average $25/day): $525
• Grand total: $1,775‑$2,425

Practical Tips

• Book all internal flights at least 3 weeks in advance; last‑minute tickets can exceed $800.
• Use a single travel credit card that waives foreign transaction fees to avoid extra charges on flight purchases.
• Carry a small amount of cash in local currency for markets; ATMs in tourist zones often have high withdrawal fees.
• Download offline maps for Cusco and Rio; mobile data can be spotty in mountainous areas.

Takeaway

If you want a three‑week south america trip that actually works, fly the long legs, stick to the visa‑friendly windows, and skip the romantic notion of overland adventure between continents — your itinerary will stay on schedule, your budget will stay intact, and you’ll actually see the sites instead of spending days in a bus.