What geographical discoveries were made by the Vikings in the 9th – 11th centuries?

The Vikings in the IX-XI centuries made a lot of geographical discoveries, given that other Europeans in those days did not swim anywhere, and the Arabs were the leaders in the southern seas, they mastered the Indian Ocean.

First, the Vikings discovered Iceland, they were able to settle it, and even one of the oldest parliaments arose there.

Secondly, they sailed to Greenland, no one swam so far north before them, not even the Romans. There were settlements in Greenland, but they did not exist for long.

And, finally, the Vikings were the first of the Europeans 500 years before Columbus and John Cabot to reach the American continent; they settled in Newfoundland, but did not last long.