Marco Polo
13th-Century explorer known best for his travels along the Silk Road and his writings about those travels

John Cabot
Known for "finding" Newfoundland for England, he was an Italian by birth.

Christopher Columbus
He was Italian, of course, but he sailed for Spain.

Amerigo Vespucci
America is named for him.

Ferdinand Magellan
He was from Portugal but sailed for Spain.