1) As far as I am concerned, bravery is such important quality. Brave person can literally wade through any sea. Nothing is impossible, you just have to hope you are up to the task at hand.
I think I am brave enough. I can admit my guilt and look danger in the face.
Another personal quality every explorer should have is aspiration to cognition. If you want to discover different places, you can not do it without an interest in the organization of the world.
2) One of the famous explorers I know is Christopher Columbus. He completed four voyages across the Atlantic Ocean and discovered the „New World” — America. Another well-known traveler you should know is Ferdinand Magellan. He led the first expedition to circumnavigate the globe.