Maglev (derived from magnetic levitation) was a system of overland, underground, and transoceanic transport used on many Federation planets, including Earth. (Star Trek: The Motion Picture, TNG: "We'll Always Have Paris", "All Good Things", DS9: "Past Tense, Part 1", VOY: "Non Sequitur")
Maglev (and later antigrav) systems all but eliminated powered wheeled vehicles -- and the upkeep and repair of the "conventional" rail systems extant since Earth's 19th century -- because it was frictionless.
- There was still a perceived need for powered wheeled vehicles, even in the 24th century, as demonstrated by the existence of the Argo all-terrain vehicle. (Star Trek: Insurrection)
During the 23rd century, the many facilities of the Empire State Hospital Complex, on Roosevelt and Manhattan Islands in New York City, were connected by an underground private maglev network. (Star Trek: Avenger)
- The maglev train in the novel was said to have a typical speed of 3,000 km/hour.
After her college boyfriend broke up with her in 2273, Carolyn Adiwoso hopped on a maglev from New York City to San Francisco to cry on her cousin Sabartomo's shoulder. (Star Trek: Shadowstar Station: "Promised")
- The term sub-shuttle was used interchangeably with maglev in this story, and derived from Gene Roddenberry's 1970s pilots Genesis II and Planet Earth.
Earth's global maglev network was active through at least the late 24th century. One of the longest routes was in the African Confederation, along the west coast from Casablanca to Cape Town. And, in Tokyo, more of the inhabitants used maglevs than transporters, even in the 2370s. (Last Unicorn Games RPG: "The Cadet's Guide to Sector 001 Earth")
After their second wedding ceremony in Seattle, Jack and Beverly Crusher preferred to take a coast-to-coast maglev from Tacoma Station to Providence, Rhode Island, rather than use transporters. ("4th and Market")
- It has not yet been seen, either in aired or published Trek, to what extent Earth's maglev network was made obsolete by site-to-site transporters. However, the existence of maglev trains didn't obviate air trams or hovercars -- though private ownership of the last might have been strictly licensed, or limited to VIPs.
The main maglev station for Starfleet Command in San Francisco was at Fort Point, underneath the Golden Gate Bridge's southern approach in 2381. (Beverly Crusher Investigates: The Death on the Kobayashi Maru)