Denver International Airport (IATA: DEN, ICAO: KDEN, FAA LID: DEN), often called DIA, is, by land size at 52 square miles (130 km²), the largest international airport in the United States, and the third largest international airport in the world after only King Fahd International Airport and Montréal-Mirabel International Airport. Runway 16R/34L at Denver is the longest public use runway in the United States. . Dallas-Fort Worth International Airport is located between the cities of Dallas and Fort Worth, and is the busiest airport in the U.S. state of Texas. In terms of land area, at 18,076 acres it is the largest airport in Texas, the second largest in the United States, behind Denver International Airport, and fourth largest in the world. .