Dade-Collier Training and Transition Airport (IATA: TNT, ICAO: KTNT, FAA LID: TNT) is a public airport located within the Florida Everglades, 36 miles (58 km) west of the central business district of Miami, in Collier County, Florida, United States. It is owned by Miami-Dade County and operated by the Miami-Dade Aviation Department. The airport is on the Tamiami Trail near the border between Dade and Collier counties in central South Florida.

Begun in 1968 as the Everglades Jetport (also known as Big Cypress Jetport), the airport was planned to be the largest airport in the world, covering 39 square miles with six runways, and connected to both central Miami and the Gulf of Mexico by an expressway and monorail line. The airport would have been five times the size of JFK Airport in New York. At the time, the Boeing 2707 was under development and it was anticipated that supersonic aircraft would dominate long-haul air transportation. South Florida was viewed as an ideal location for an intercontinental SST hub due to the limitation that such aircraft would have to fly over water. Because of environmental concerns and the cancellation of the 2707 program, construction was halted in 1970 after the completion of just one 10,500' runway.

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