In 1492, Christopher Columbus discovered the Americas. Except, of course, for all the people who already lived there. Shoot, he wasn't even the first European to arrive the Americas.
So what lands did the Europeans actually discover? What lands did they arrive at first before any other humans? Bill Rankin made this map and chart showing the locations, dates and current populations of lands that Europeans can legitimately claim to have discovered. You can view a larger version at the link.