(Photo by Jordan Barab)

For the sixth year in a row, the most convenient airport to Washington, D.C. hit a new passenger record. 23.6 million people flew through National Airport in 2016, an increase of 2.4 percent over the year prior, the Metropolitan Washington Airports Authority announced today.

While American remains the largest carrier to serve DCA, increases on Southwest, Delta, United, JetBlue, and Frontier were responsible for the growth.

National is now serving millions more passengers than it was designed for, and MWAA has had to make major accommodations. After years of discussion, $1 billion project is now in the works to create a new commuter concourse on the north side.

Washington Dulles International, meanwhile, is behind DCA in passenger arrivals, though it is over 10 times bigger. Still, figures from last year also show growth, including a new record for international travelers and slight increase in domestic passengers. In total, Dulles served 22 million people last year.

MWAA is also in the midst of a four-year effort to improve the amenities at both airports, adding more than 100 new restaurants and shops.

Meanwhile, Baltimore/Washington International Thurgood Marshall Airport, which is not run by MWAA, also had a record-setting year. Maryland Governor Larry Hogan announced last week that 25.1 million people flew through BWI in 2016.