Beyond Monte Dinero, the road improves as it approaches Cabo Vírgenes, second only to Punta Tombo among Argentina’s Magellanic penguin colonies. With more than 120,000 breeding pairs, the rapidly growing colony has increased by at least a third in a decade-plus.

The abundance of brush here means the birds are less visible than at Dos Bahías, and there’s no direct beach access. A 1,500-meter nature trail, though, permits close approach to the birds, and there’s an interpretive brochure in good English. There’s an admission fee of US$5 for foreigners, less for Argentine and Santa Cruz residents.

At the reserve’s northeast corner, the rehabbed hilltop Faro Cabo Vírgenes, the historic Argentine lighthouse, includes a small museum. Outside, facing the ocean, there remain foxholes dug to repel British commandos who might have landed here during the 1982 Falklands aar (Britain conducted operations in Argentine Patagonia and Tierra del Fuego, escaping into Chile with collusion from the Pinochet dictatorship, which feared an Argentine attack if the Brits lost).

At the so-called Cementerio Histórico, the only truly legitimate tomb may be that of Conrado Assinbom, a hermit who lived in the shack beneath the lighthouse. One older cross is almost illegible, and it’s not certain anyone’s buried there.

At the reserve’s southern edge, visitors can cross the border—technically illegally—to see Faro Punta Dungeness (1897), the lighthouse at the east end of Chile’s narrow latitudinal strip along the Strait of Magellan. When duties permit, Chilean navy personnel show visitors around the facility.

Estancia Monte Dinero has the nearest accommodations, and its sparkling confitería Al Fin y al Cabo has become the place to stop for lunch and sweets—try the rhubarb cake with calafate sauce. While it’s fairly expensive, the quality is excellent and the building has magnificent shoreline views south to Cabo Dungeness.