Just How Tall Can Roller Coasters Get?

THIS IS NOT A RHETORICAL QUESTION THESE DAYS. Theme parks have engaged in a dizzying quest for height in recent years that has spawned a number of roller coasters as tall as skyscrapers. Altitude rather than velocity has become such a defining characteristic that rides that take advantage of their soaring heights have been given a name befitting a mammoth frame: the giga coaster.

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