With the hustle and bustle of parking, security lines, departures, and arrivals, every traveler knows that airports are usually busy places. Especially true for large or international airports, the mix of passengers from different countries and cultures combined with the stress of trying to check bags, print boarding passes, and get to your gate on time creates an atmosphere of excitement and anticipation. You'll find all these things and more at the busiest airports in the United States.

01O'Hare International Airport, Chicago

The colored electric neon tunnel The Sky Is the Limit at Chicago O'Hare International Airport

When it comes to being named the busiest airport in the U.S., it turns out there is fierce competition for the top spot. Airports are evaluated based on the number of "flight operations," which can include commercial airline flights, general aviation flights, military flights, and air taxi operations. However, another measure to determine business is the total number of passengers served by the airport. The most recent data from the FAA shows that O'Hare International Airport in Chicago was the U.S. airport with the greatest number of flight operations in 2018 with over 903,000 arrivals and departures. United Airlines, O'Hare's largest carrier, added many flights from the Chicago hub to other domestic destinations, helping to put O'Hare on top.

02Hartsfield-Jackson Atlanta International Airport

Passengers are walking on the walk way in Hartsfield Jackson Atlanta International airport

Hartsfield-Jackson International Airport in Atlanta is often considered the busiest airport not only in the U.S. but in the world. This is because it boasts an annual passenger count of over 100 million people, making it the undisputed busiest airport when it comes to passenger volume. In 2018, this Delta hub hosted more than 895,000 arrivals and departures. Why is this airport so busy? Around 80% of U.S. residents live within a 2-hour flight of Hartsfield-Jackson. This makes it an ideal connection spot for both domestic and international travelers.

03Los Angeles International Airport

People walking in the arriving and depurating area of the Los Angeles International Airport

Commonly known by its airport code LAX, the Los Angeles International Airport is typically considered the third-busiest airport in the U.S. This Southern California airport typically serves around 84.5 million passengers each year, especially travelers headed out west, island-hopping to Hawaii, or bound for even more exotic locations in Asia. In fact, LAX even has an international terminal that is dedicated to travelers from Japan, China, and other Pacific countries.

04Dallas-Fort Worth International Airport

Dallas Fort Worth International Airport, Dallas, TX, USA

They say that everything's bigger in Texas, and when it comes to airports that certainly seems to be true. Texas is home to three airports that rank in the top 35 busiest in the U.S. But the top spot in the Lone Star state goes to the Dallas-Fort Worth International Airport. Often abbreviated DFW, its airport code, this busy airport is the major hub for American Airlines. Thanks to its hub status and its location, DFW typically serves around 65 million people each year.

05Denver International Airport

Denver International Airport

The fifth-busiest airport in the U.S. is the Denver International Airport in Colorado. Locals refer to it as DIA, though its airport code is DEN. Nearly 64.5 million people travel through this airport each year.DEN serves as a gateway to the Rocky Mountain region. Fantastically its the largest airport in the U.S. by total land area. And the second-largest in the world. Denver International Airport serves as Southwest Airline's main operating base and is also a major hub for United and Frontier.

06John F. Kennedy International Airport

the hall of John F. Kennedy International Airport

It's no surprise that the biggest city in the United States is also home to one of its busiest airports. John F. Kennedy International Airport, located in the Queens borough of New York City, is usually considered the sixth-busiest airport in the U.S. A common entry destination for travelers from Europe coming to the U.S., this airport even has a pet-only terminal called the ARK at JFK. It also has a special runway for to Air Force One as well as an extra-long runway that was a backup landing spot for NASA's space shuttles.

07Charlotte Douglas International Airport

Waiting area in Charlotte Douglas International Airport

Charlotte Douglas International Airport in North Carolina is a little different from other busy U.S. airports since it is a joint civil-military public international airport. After DFW, it is the second-largest hub for American Airlines. Passengers heading to the Caribbean islands for vacation often travel through this airport. Popular destinations include Belize, Punta Cana, Freeport, and St. Croix. CLT is home to the Charlotte Air National Guard base and the 145th Airlift Wing of the NC Air National Guard.

08San Francisco International Airport

Front facade and entrance to SFO, San Francisco International Airport terminal passenger unloading zone

San Francisco International Airport is the largest airport in northern California and one of the busiest airports in the U.S. thanks to its status as a major gateway to European and Asian destinations. SFO serves as the home of start-up airline Virgin America and is a hub for United Airlines and Alaska Airlines. Visitors enjoy touring the SFO Museum which features permanent artwork as well as temporary exhibitions in more than 20 galleries.

09McCarran International Airport

McCarran International Airport in Las Vegas NV

McCarran International Airport in Las Vegas, Nevada, is a major hotspot for passengers traveling to amazing destinations in the U.S. west including the Hoover Dam, Zion National Park, and the Grand Canyon. LAS is technically located in Paradise, Nevada, around five miles from Sin City. Interestingly, it is the major airport in the region for both public and military use. Several smaller airlines, including Allegiant, Frontier, Southwest, and Spirit, use McCarran as a service or maintenance hub.

10Seattle-Tacoma International Airport

Tacoma International Airport, Seattle

The Seattle-Tacoma International Aiport, commonly nicknamed the Sea-Tac airport, is the busiest and largest airport in the Pacific Northwest. The primary hub for Alaska Airlines, this airport also serves as a major international gateway for Delta Airlines. Sea-Tax serves destinations in Europe, Asia, and the Middle East. Operated by the Port of Seattle, this airport features multiple art installations at each concourse to help entertain travelers during layovers.