Labor Day (US)

Labor Day is an American federal holiday which is observed on the first Monday of September. The holiday originated on September 5, 1882 as the Central Labor Union of New York City sought to create a day off work for the working citizens. For most Americans, Labor Day now marks the end of the summer and is the last day of a three-day weekend.

See http://usafederalholidays.com/labor-day/ for more information.