If you ever go to Ushuaia you'll probably want to head to where the glacier lived a few years ago before melting away. You should not take a taxi to the chairlifts and then take the chairlifts up. You should walk the entire way, which may take you 8 hours, but it is worth it. There is a beautiful trail that will take you up the mountain to the glacier. It was one of the hardest most frustrating hikes of my life, but it was also the most wonderful place. Here's some photos of trees from that hike.
The panopticon prison was built primarily to accommodate relapsing prisoners, but ended up housing some of Argentina’s most dangerous criminals. It’s through the labor of the prisoners that the bulk of the town was built.
Ushuaia is the most southern city in the world at the very tip of Argentina. You must go through Chili to get there and take a Ferry to Tierra del Fuego which you are followed by lots of Commerson Dolphins. There is also a grand total of 4 boarder crossings just to get there.