On Feb. 24, we flew from Buenos Aires to Ushuaia, the southernmost town in Argentina. Tourism is the sole purpose for Ushuaia's existence. There is some local skiing in the nearby mountains, but the town's main business seems to be as a jumping off point for cruises through Tierra del Fuego and to Antarctica.
(We decided to pass on the Antarctic cruise thing. Expensive, culminates in a very short period ashore on ice, and consists of two days each way in some of the planet's roughest seas.)
The next day, we boarded the Mare Australis (total passenger count of 109 passengers) in Ushuaia, headed south for about two hours for a brief stop at Chilean immigration and customs, then continued south all night to the southernmost tip of land north of Antarctica--Cape Horn. In the morning, we boarded Zodiac dinghies and landed on the lee side of the island, climbed to the top, and got blasted by 100-knot+ winds at the top. We visited the lighthouse (manned by an Chilean sailor and his family for a 1-year tour of duty), and a beautiful albatross sculpture dedicated as a monument to the 800 ships and 10,000 sailors lost in the Cape Horn area.