Sadly, this doesn't reference a long-forgotten wizard founder. Miami is called the Magic City because it became a city seemingly overnight. Here's what happened: a wealthy widow purchased a citrus plantation and moved there before it was much of anything. She convinced her rich and powerful friends to extend the railroad down there, build streets and power systems, and add a resort. By 1896, the city was incorporated, and pretty soon, people were moving there (and visiting) in droves. Good work, Julia Tuttle.
City of Angels
Los Angeles, CA
We really hope your Spanish comprehension is basic enough to figure this one out.
Seattle got its Frank L. Baum-esque name from a 1982 contest held by the Seattle-King County Convention and Visitors Bureau. The group challenged the public to come up with the best nickname for the city, and Emerald City won out. It's easy to see why, considering the fawning entry described Seattle as, "the jewel of the Northwest, the queen of the Evergreen State, the many-faceted city of space, elegance, magic and beauty."