 Cincinnati/Northern Kentucky International Airport is the largest airport in the state, and is a focus city for passenger airline Delta Air Lines and headquarters of its Delta Private Jets.The airport is one of DHL Aviation's three super-hubs, serving destinations throughout the Americas, Europe, Africa, and Asia, making it the 7th busiest airport in the U.S. and 36th in the world based on passenger and cargo operations.CVG is also a focus city for Frontier Airlines and is the largest O&D airport and base for Allegiant Air, along with home to a maintenance for American Airlines subsidiary PSA Airlines and Delta Air Lines subsidiary Endeavor Air.