In 1963, French engineer Jean Bertin presented a 1/12 scale model of his idea for an Aérotrain, a jet-propelled monorail train which would float on a cushion of air to eliminate friction and allow for unprecedented speeds.
Bertin built four prototypes of his Aérotrain, from a half-scale, 30-foot version with room for four passengers, to a full-sized, 75-foot version with a car for 80 passengers.
In 1974, the latter prototype, the Aérotrain I80, set a world speed record for overland air cushion vehicles, reaching a mean speed of 259.5 miles per hour and a peak speed of 267.4 miles per hour.
Plans were made and contracts were signed for the Aérotrain to enter service in the Paris area, but when funding dried up and Bertin died in 1975, the project was scrapped, leaving miles of elevated test tracks abandoned in several locations in France.
The Aérotrain was a forerunner to modern maglev (magnetic levitation) trains, which use magnets to float above the rails and reach speeds of up to 270 miles per hour.


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