Answer :

Although it's a bit counter-intuitive, Columbia actually never explored North America, instead visiting the other locations on this list instead. This lead to great discoveries but lots of suffering for the local inhabitants. 
GalaxyGamingKitty

Columbus never explored North America.

But, here is who did explore North America: Several theoretical contacts have been proposed, but the earliest physical evidence comes from the Norse or Vikings. Erik the Red founded a colony on Greenland in 985 CE. Erik's son Leif Eriksson is believed to have reached the Island of Newfoundland circa 1000, naming the discovery Vinland.