Hey, two days in Ushuaia were just enough for us… We arrived at night and found a hostel where there were actually a couple of people staying despite the frigid cold. We figured this place would be deserted because its really between the Summer travel season and Winter ski season.
To cross to Tierra del Fuego you have to cross the Straight of Magellan or Estrecho de Magallanes at Bahia Azul (blue bay). The ordeal was pretty nifty and cold, we waited for the ferry to arrive while looking into the clear waters seeing straight (heh, heh, heh) down to the bottom, someone said they saw a small whale, but I missed it.
Tierra del Fuego, the Land of Fire is the huge island group at the very tip of the southern cone of South America. The majority of the area is claimed by Chile but the two big cities there are on the smaller Argentinian side: Rio Grande and Ushuaia, the later of which is the proported southern-most city in the world somewhere around 53° Latitude.