My wife and I are spending several days in Ushuaia (after an Antarctic cruise) and she loves penguins. We know that king penguins are unlikely to see on the cruise, so were wondering if there is anywhere within day trip range from Ushuaia where one can reliably see them in the wild?
This article about nearby Isla Martilla discusses some of the opportunities available for penguin viewing. It seems this island is easy to get to from Ushuaia by boat, and will almost certainly have penguins, although it doesn't look certain that you'll see king penguins.
King penguins are also found seasonally at the Falkland Islands, but that would not be a trivial day trip from Ushuaia.