San Antonio International Airport — San Antonio, United States

Serving Texas's second-most populous city, SAT handles a surprisingly modest volume of traffic relative to San Antonio's size, functioning mainly as an origin-and-destination airport rather than a connecting hub for any major carrier. The airport sits north of downtown, within easy reach of the Alamo, the River Walk, and the military installations that have earned San Antonio its longstanding nickname, Military City USA, tied to bases such as Joint Base San Antonio and historic Fort Sam Houston. Tourism linked to the city's Spanish colonial missions, five of which collectively hold UNESCO World Heritage status, brings a steady stream of domestic visitors through SAT year-round. The airport has undergone repeated terminal expansions to keep pace with the metropolitan area's rapid population growth, among the fastest of any major American city. International service remains limited mostly to nearby Mexican destinations, leaving longer international trips typically routed through Dallas or Houston.