Columbus Day did not become a Federal holiday until 1937 although some localities have honored the day since the 18th Century. Observance of the day is meant to honor Columbus' achievements, but in recent years the day has become controversial.
Columbus did know that the world is round, but it was thought that only the Atlantic lay between Europe, Africa and Asia (old world). It was only after further exploration that cartographers realized that Columbus had reached new continents (new world) not connected to the old world.
Ernster, the Virtual Library Cat
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