The largest of all the Disney complexes, Disney World in Florida covers a massive 30,080 acres (12,173 ha) and is the number 1 most visited theme park complex in the world.
Initially opening in 1971, the resort complex is made up of four theme parks, two water parks, twenty-four themed resorts, five golf courses, and several additional recreational and entertainment venues.
The main 4 theme parks are: Magic Kingdom, Epcot, Disney's Hollywood Studios and Disney's Animal Kingdom each with their own distinct theme and attractions.
Magic Kingdom is the main attraction, dedicated to Disney characters and fairytales and is made up of 6 "lands": Main Street, USA, Adventureland, Frontierland, Liberty Square, Fantasyland and Tomorrowland.
Fantasyland recently completed a major upgrade in December 2012 including a new "Storybook Circus" area featuring characters from Dumbo and the Mickey Mouse universe, including an upgraded "Dumbo the Flying Elephant" ride and "The Barnstormer featuring the Great Goofini".
Epcot was originally planned by Walt Disney in 1965 to be an "Experimental Prototype Community Of Tomorrow" - a real, operating, experimental city of 20,000 people utilizing the latest technology to test new ideas and concepts for urban living. Disney died before his vision was realised, with Epcot eventually opening in 1982 as a "Permanent World's Fair" inspired by his original vision.
Being in Florida, the sub-tropical weather means it will generally be warm (which can't be said for all Disney parks!), ranging to hot and humid during summer (May–October) and late afternoon thundershowers are common June-September, however the park is well-equipped to deal with this regular occurrences.
The peak periods for crowds are late December, mid-June to mid-August, and mid-February to mid-April, which correlates with school-breaks, so if you're after for a quieter experience, plan accordingly.