Southwest Florida International Airport is a major county-owned airport in the South Fort Myers area of unincorporated Lee County, Florida, United States. The airport serves the Southwest Florida region, including the Cape Coral-Fort Myers, Naples-Marco Island, and Punta Gorda metropolitan areas, and is a U.S. Customs and Border Protection port of entry. It currently is the second-busiest single-runway airport in the United States, after San Diego International Airport.