On October 1st, 1971 the happiest place on earth opened up in Florida..."Disney World"!  It is the most visited such complex in the world. So why did Walt Disney choose Orlando, Florida?

Well he was looking for a place to create a larger, roomier version of his theme park in Anaheim but Orlando, at the time, was mostly swampland and a stat showed that only 2% of people east of the Mississippi river came out to California.

They considered Niagara Falls, but ultimately scratched the idea it because the frigid winters would prevent them from staying open year-round. They decided southeast was the way to go. With an eye on Florida because swampland was cheap there.

And in case you’re wondering how Disney managed to pull off building on top of a swamp, well... he kind of didn't. Get this, he made a big mound of dirt from what was scooped out to make the Seven Seas Lagoon, then built his theme park on top of it. When you’re walking into the Magic Kingdom, you’re actually on the second floor. The first floor is under your feet - it’s full of tunnels and buildings that allow cast members to move around the lands without being seen.

(nationalgeographic.com)