Stapleton, Denver Lake Nature Center, one of the nation's largest urban wildlife refuges. As of 2018, Stapleton has a population of around 75,000 residents living amongst 23,500 households. The Northfield section of the development (north of Interstate 70) still has significant residential and commercial development occurring today. The University of Colorado A-Line directly connecting Denver Union Station downtown to Denver International Airport started operating in 2016 and has one stop in Stapleton; the Central Park Station. Stapleton is served by the Central Park commuter rail and bus station, with direct connections to Union Station in downtown and the Denver International Airport via
Pittsburgh International Airport from the rest of the airport. While US Airways made immense cuts in service during the early 21st century, other carriers began to play a more dominant role at PIT. The airport's operator, the Allegheny County Airport Authority, has attempted to attract new service to the airport, particularly low-cost and international carriers. AirTran Airways, which had trouble competing in Pittsburgh after beginning service in 2000, was able to expand Pittsburgh offerings after the US Airways cuts. In 2003, USA3000 Airlines began service to Florida and subsequently expanded to include international destinations in the Caribbean. Southwest Airlines began service to Pittsburgh