In its nearly three million square kilometers, Argentina can offer an astonishing diversity of natural environments, starting with the Río Paraná Delta barely half an hour from downtown Buenos Aires. Ascending the Paraná and the Uruguay Rivers, several national parks have similar concentrations of birds and aquatic life, but the real can’t-miss is the Esteros del Iberá marshes, in Corrientes Province, where the colorful subtropical birds, reptiles, and mammals are reason enough to visit Argentina for a week or more. For wildlife-watching, the famous Iguazú Falls finish a distant second.

To the south and west, the Atlantic coastline and marshy grasslands of Buenos Aires Province are home to shorebirds and many other species that will be new to visitors from the Northern Hemisphere.

The cradle of biological diversity is the front-range yungas cloud forest of the northwest, but the rugged Andean terrain creates micro-environments that range from red desert canyons to scrubby high puna, where the condor soars over dormant volcanic cones. In the winter dry season, itineraries are easy to stick to, but the wet summer can disrupt overland transportation.

In the Cuyo provinces, the highlights are the desert paleontological parks at Ischigualasto, Talampaya, and Las Quijadas, worth several days. Northern Patagonia has its own paleontological circuits in and around the city of Neuquén, an accessible excursion from the lake district, and in and around the city of Trelew, near Puerto Madryn and the wildlife mecca of Península Valdés.

Nearly the entire Patagonian coastline abounds in wildlife like elephant seals, penguins, and sea lions, but the great distances require time and money to see them—public transportation is fine along the main highway, but poor off it. The same is true of the Patagonian steppes, home to the llama-like guanaco and the ostrich-like rhea, and the forests of the southern Andes beyond the main tourist clusters. In terms of its natural assets, Tierra del Fuego is a southern extension of Patagonia.

Day 1
Arrive at Aeropuerto Internacional Ministro Pistarini (Ezeiza) and transfer to a Buenos Aires hotel. Visit main historic sites.

Day 2
Take a full-day tour to the riverside suburb of Tigre and the Río Paraná Delta, including the island of Martín García near the Uruguayan border.

Day 3
Early morning flight to Puerto Iguazú, with the afternoon at the falls; if the timing’s right, take the full-moon tour.

Day 4
Overland transfer and overnight at Yacutinga Lodge, a distinctive accommodation on a private nature reserve east of Puerto Iguazú.

Day 5
Return to Puerto Iguazú and, time permitting, take an excursion to the Brazilian side of the falls.

Day 6
Overland to the city of Posadas, with a stop at the landmark Jesuit mission at San Ignacio. Continue on to Colonia Carlos Pellegrini, in the Esteros del Iberá wetlands, by 4WD vehicle with driver.

Day 7
Full-day wildlife-viewing excursion among the floating islands of the Esteros del Iberá.

Day 8
Travel overland to the provincial capital of Corrientes to catch a flight back to Buenos Aires and on to the colonial city of Salta.

Day 9
Overland loop, by rental car, from Salta up the Quebrada del Toro to the altiplano at San Antonio de los Cobres, stopping at enormous salt flats, and then descending to Purmamarca or Tilcara for the night.

Day 10
Excursion to the archaeological sites and colonial monuments of the Quebrada de Humahuaca, a World Heritage Site in Jujuy Province. Return to Salta.

Day 11
Full-day excursion to the yungas cloud forests of Parque Nacional El Rey.

Day 12
Depart by rental car for the town of Cafayate via the colorful desert canyon of the Quebrada de Cafayate, with a side trip to the pre-Columbian ruins of Quilmes. Taste Cafayate’s unique white wine, Torrontés, at any of several local bodegas.

Day 13
Return loop to Salta via the scenic village of Cachi, Parque Nacional Los Cardones, and the precipitous canyon known as the Quebrada de Escoipe.

Day 14
Morning flight to Buenos Aires, continuing to San Carlos de Bariloche. Late-afternoon excursion to Circuito Chico, in Parque Nacional Nahuel Huapi.

Day 15
Day trip by bus or rental car to Villa la Angostura; boat excursion to Parque Nacional Los Arrayanes, returning by footpath to Villa la Angostura.

Day 16
Travel by bus or rental car to El Bolsón, with a visit to its Feria Artesanal for organic beer and grazing at various food stands. Take an afternoon excursion to nearby Parque Nacional Lago Puelo or, with an early enough start, hike to the summit of Cerro Piltriquitrón for spectacular views of the Andes along the Chilean border, to the west.

Day 17
Bus or rental car to the city of Esquel, gateway to Parque Nacional Los Alerces and its millennial alerce forests. Spend the afternoon at the ski area of La Hoya, where the chairlift carries hikers to the trailheads in summer.

Day 18
Boat excursion (Circuito Lacustre) at Parque Nacional Los Alerces, with an overnight at the park’s landmark Hotel Futalaufquen or in more modest accommodations, including camping.

Day 19
Return to San Carlos de Bariloche, stopping at Butch Cassidy’s former cabin, with a detour to Parque Nacional Nahuel Huapi’s Ventisquero Negro (Black Glacier).

Day 20
Return flight to Buenos Aires, with the afternoon and evening free for sightseeing and perhaps a tango floor show.

Day 21
Full day for exploring Buenos Aires before an evening departure.