Americans are celebrating Columbus Day today. Columbus Day is a federal holiday observed on the second Monday in October, marking the anniversary of arrival of Christopher Columbus to the Americas. Columbus, an Italian explorer sailing under the Spanish flag, led four expeditions to the New World, but never accomplished his original goal, to find a western ocean route to Asia.<br/><br/>Instead, Columbus ushered in a new era in world history by opening up the Americas to exploration. Columbus Day became a U.S. holiday in 1971. It is generally observed by banks, the bond market, the Postal Service and other federal agencies, along with most state government offices and some school districts. However, many businesses and stock exchanges remain open. <br/><br/>