Casper is a city in and the county seat of Natrona County, Wyoming, United States. Casper is the second largest city in the state, according to the 2010 census, with a population of 55,316. Only Cheyenne, the state capital, is larger. Casper is nicknamed "The Oil City" and has a long history of oil boomtown and cowboy culture, dating back to the development of the nearby Salt Creek Oil Field. In 2010, Casper was named the highest-ranked family-friendly small city in the West, and ranked eighth overall in the nation in Forbes magazine's list of "the best small cities to raise a family".
Source: Wikipedia (as of 04/11/2019). Read more from Wikipedia