Christopher Columbus set sail from Spain in October 1492, and arrived in America off the coast of one of the Bahamas islands. He technically did not discover America, as the Vikings had been in Newfoundland, Canada, four centuries prior to Columbus' journey.
At the time, Columbus did not actually think he was in a new, yet undiscovered continent, but rather he believed that he had reached the eastern shores of India. The premise of his voyage was to find a quicker way to reach Asia without having to sail around the coast of Africa or make a dangerous journey over land. Columbus would return two more times after his initial voyage to America.