One of my favorite interviews from the Darwin book was with a naturalist who lives in Tierra del Fuego, who talked about wanna-be explorers showing up in Ushuaia (T del F's largest city, population 60,000), and looking around at the cafes and bookstores and cruise ships and thinking, "You mean, I'm not the first?" So no, you're not going to be the first person to visit Tierra del Fuego, and although it's the end of the continent in the geographical sense, it's actually a lot less isolated than most of Patagonia. Still, there's fun to be had, particularly if you're feeling juvenile -- which, with the right traveling companions, isn't very hard at all. Here's a quick story about the southernmost place I've ever been.

	The end of the southernmost highway in the world.

The unpaved road to the edge of South America winds along the southern tip of the island of Tierra del Fuego, past grazing cattle, past trees bent double like hunched old women by the unflagging wind, past swarms of Patagonian geese and black-billed ibises that watch our car with idle, unhurried curiosity. We are playing a game here, and so are a healthy number of tourists in Ushuaia, Argentina: We are recording "southernmost" experiences.

It is at once the most charming and most addictive part of the half-day drive around the southern end of the Isla Grande de Tierra del Fuego: Every mundane thing has become, somehow, the southernmost mundane thing we've ever done, and therefore significant, like downing our southernmost-consumed beers at the excellent brewery on the shores of the Beagle Channel (and, soon thereafter, recording our southernmost-visited men's room).

It's late on a spring afternoon, but we're far south and the sun is high, flickering in and out of behind a net of high clouds, setting the ocean aglow in spots like beams from a magnifying glass focused on the choppy surface. We edge along a ridge, squeezed on the high road between ominous rock face and chessboard-patterned ocean, and it is there we see the dead cows.

No one clears the bodies off the road out here; not that it's that hard to get here, but nobody seems to come here anyway, so by the time our right front tire connects with the first skull it has dried out enough to go "crunch." My friend Patrick, looking back gleefully, says, "That was definitely the southernmost carcass I've ever run over." His friend Lynn groans and rolls her eyes in the back seat, and he adds, "Also the southernmost skull I've ever crushed."

	The Estancia Harberton, in Tierra del Fuego.

It was cheerfully sunny in Ushuaia this afternoon as we rattled 70 miles out of town toward the oldest ranch in Tierra del Fuego, Estancia Harberton. A storm had blown through the day before, leaving the mountains surrounding the city cloaked in white, with caps of craggy rock poking out from the folds of snow. When we drove out to explore the countryside in our rental car (our southernmost car rental), we found thick drifts stacked along the side of the highway, veiling the surrounding trees.

We followed a washboard dirt road away from the main highway, ducking through pine forests and opening onto wind-scoured cattle grazing land. Huge swaths of dead, ghostly trees, bark bleached into a bone-white, spilled into small lakes, testament to the scourge of Tierra del Fuego, the beaver. Introduced from Canada in 1946 for pelt-hunting, the chewing rodents have spread forth, and without any predators their insatiable hunger for trees and dams is destroying the landscape. We soon spotted the southernmost beaver any of us had ever seen; a small black knob of fur streaming away from us across a charcoal-colored lake, leaving a little wake behind it.

Estancia Harberton has mostly switched from ranching to live off its 8,000 tourist visits a year, and we settled into the appropriately rustic dining room for afternoon tea. Tommy Goodall, the 71-year-old manager, and great-grandson of the first western missionary in Tierra del Fuego, plucked at his overalls as he greeted us and brought us small lemon cakes to complete our southernmost tea.

Goodall stared out the huge windows overlooking a cobalt finger of the Beagle Channel and mined his considerable memory to tell us stories about the ranch, the beavers, the island and his family. In 1860 his great-grandfather, Thomas Bridges, came here to teach the locals Christianity. Bridges became famous for writing a dictionary of the indigenous language, but his work did less to bring people to Tierra del Fuego than Goodall’s father, John Goodall, who planted trout in the streams around the estancia. The island now has some of the finest trout fishing in the world. At 55 degrees south latitude, it is an excellent place to catch your southernmost-ever trout.

	Patrick and I, posing on the bluffs at the southern end of Tierra del Fuego.

After tea we climbed back into the car and drove southeast past Harberton, along the shores of the channel. Twenty miles out the map showed the road ending, but we found a gate, a bridge over a small creek tumbling down a forested crack in the cliffs, and continued. There we crossed paths with the dead cows, noted the peculiarly southern nature of our encounter, and drove on.

Between flickering pine trees we catch flashing glimpses of the deep blue of the Atlantic Ocean and the deep green silhouette of Staten Island. A sharp shore break pounds the rocks along this stretch of the channel into perfectly polished marble ovals that glitter with hints of orange and yellow. As each wave recedes, the stones clatter and roll, like cards strapped to the spokes of a bike.

Checking the map, we see that we've gone further south than Puerto Williams, a Chilean naval settlement across the channel from Ushuaia that claims the "southernmost town in the world" distinction. We find a long point and walk out on the bluffs overlooking the beach, toward the sandy edge and the 20-foot plunge into the kelp-filled water below. At last, toes on the nose, we turn and look north. If we don't make it to Antarctica, this is as far south as any of us will ever go. Lynn points a camera at us, and Patrick and I smile as a wave crashes up off the rocks and, as the spray falls back into the glittering water, Patrick whispers out of the corner of his mouth, "I'm further south."