Harry Reid International Airport is the main government airport for public use in the Las Vegas Valley, a metropolitan area in the U.S. state of Nevada. It covers 2,800 acres (1,100 hectares; 4.4 square miles; 11 square kilometers) of land and has four runways and two passenger terminals. The airport was built in 1942 and opened to airline flights in 1948. It has expanded and employed various innovative technologies, such as common-use facilities.