El Calafate, Argentina ? For our 6-year-old, it’s the whales — a mother and baby greeting us by raising their tails side by side out of the chilly South Atlantic.

Our 4-year-old votes for the penguins — thousands of them, teeter-tottering between their nests and the sea to answer the cries of their fuzzy twin newborns.

For my wife, it’s either the black-and-white dolphins racing past our speedboat, or the awesome sight and thunderous sound of the Perito Moreno glacier spawning icebergs the size of city buildings.

For me, the highlight of our 10-day, once-in-a-lifetime tour through Patagonia, the extreme southern tip of South America, came on the back of a lively pinto named Caramelo as I rode through an icy rain.

My wife — a native of Buenos Aires — arranged hotel stays and tours in Puerto Madryn, Ushuaia and El Calafate, towns that serve as launching pads for Patagonia’s natural wonders. Some people thought we were crazy to bring two boisterous boys along, but they held up well, excitedly spotting guanacos (a cousin of the llama), ostrichlike choiques and rare Andean condors as our drivers zoomed along gravel roads at 60 mph.

We packed familiar toys and snacks to fend off tantrums, but wherever we went, our boys were entertained by adults who gave them candies and attention. It’s a wonderful thing about Argentine culture, this understanding that kids need to be kids, not miniature adults.

But we didn’t anticipate how the long summer days of December would affect their sleep. So close to the South Pole, with 20 hours of daylight, it was difficult to convince our 4-year-old that it really was bedtime after 10 p.m.

And just when the kids finally crashed, Argentines were hitting the town — restaurants busily set tables for families at 11 p.m., waitresses holding babies so mothers could eat.

Their secret is the siesta — a rejuvenating nap still respected in much of the country, with stores and offices closing each afternoon. We had no time for such rest — there was too much to see.

A tourist visits the Perito Moreno Glacier, the largest in Patagonia. The glacier falls spectacularly into Lago Argentina at its western end. It is the only nonreceding glacier in the world.

After our 17.5-hour flight from San Francisco to Buenos Aires, the other flights were short hops. From the regional airport in Trelew, a driver took us through the desert to Puerto Madryn. We stayed at the Hotel Tolosa, a sleek place with excellent service.

A taste of everyday life

Puerto Madryn sits on the Golfo Nuevo, where southern right whales give birth each spring, just south of Peninsula Valdez, a land mass that attracts elephant seals, sea lions and other seals and birds. The world’s largest colony of Magellanic penguins, at 800,000 and growing, is 125 miles to the south on Punto Tombo.

Puerto Madryn is a growing city, with lower prices ($30 for enough llama wool to knit a sweater), and more opportunities to mix with everyday Argentines than in some other tourist spots. Window-shopping our way to the beach, we passed a joyful convoy of soccer fans celebrating the Boca Juniors’ latest victory, and just when our kids began to wilt in the heat, we found Helados Kebom, an ice cream shop with a small playground. Argentine ice cream is not to be missed — richer and tastier than anything in the States.

We also visited the Museo Egidio Feruglio in Trelew, with impressive exhibits of dinosaur fossils pulled from the nearby bluffs. Then it was off to the world’s southernmost city, in Tierra del Fuego. Settled initially to assert Argentina’s territorial claims in border disputes with Chile, Ushuaia still feels like a remote outpost between the Andes and the sea.

We took a tour through mountain passes that included a stop at a lodge where sled dogs are trained; a hike to Lago Escondido; and a meal of “cordero Patagonico” — lamb roasted on iron crosses over a wood fire. We worked off lunch by exploring a stream in the “turba,” a kind of peat moss that is 90 percent water, so thick and spongy it feels like bouncing on a trampoline.

Magellanic penguins are seen near Puerto Madryn, Argentina. The penguins inhabit the cold temperate waters and subantarctic regions of coastal Chile and Argentina.

The kids loved the next day’s trip, on the “Tren del Fin de Mundo,” a steam engine carrying tourists into the national park, through breathtakingly beautiful valleys, past waterfalls and wetlands that provide a surprisingly green contrast to Patagonia’s stony dry steppes.

Natural strength

By the time we landed in El Calafate, we were tired of tour buses but eager to see the glaciers. First we splurged on an excellent meal at Barricos del Enopio — stuffed rabbit and Patagonian trout with a fine Argentine chardonnay, and delicious pumpkin soup for the boys. The chef also agreed to make an off-menu platter of breaded meat and mashed potatoes to calm their bellies after so many days on the road. All that for $42, the most expensive meal of our trip.

Given the dollar’s strength in Argentina — $1 buys three pesos — we were surprised to encounter no Americans. But we were also saddened to see few Argentines in the national parks. The country is slowly emerging from an economic crisis; most locals can’t afford to see their own Yosemites and Yellowstones.

The Perito Moreno glacier rises 200 feet above the water and pushes against a rocky peninsula, creating tremendous pressure. It’s hard to imagine a land form three miles wide being constantly in motion, but every few minutes, we heard the pistol-cracks of icebergs breaking off. To the sound of rolling thunder, we saw a huge blue iceberg rise up from the lake and launch itself off the glacier’s face.

The next day, we rose at 5:30 a.m. for a spectacular boat trip on the Upsala Explorer to another glacier and the Estancia Cristina, a former sheep ranch frequented by scientists and trekkers.

Our kids weren’t old enough to ride the horses, so they explored the gardens with my wife while I climbed onto Caramelo and headed into the Andes with other riders. An icy rain blew through. Then the clouds parted, revealing the imposing heights of the 8,956-foot Cerro Norte.

When we reunited in the estancia’s grill house for another unforgettable meal, the boys excitedly displayed old sheep bones they’d found. For the whole family, it proved to be a grand adventure.