The Largo, Maryland theme park originally opened as a water park in 1981 with the name Wild World (supposedly because it was founded by Jim Fowler, the assistant on Wild Kingdom). It featured a number of waterslides and a wave pool, with just a couple of dry rides - a ferris wheel, giant swings, teacups, and the like. When Boston's Paragon Park closed in 1985, the Giant Coaster - which had operated there since 1917 - was moved to Wild World, where it was renamed the Wild One and began service in 1986.

More dry rides were added during the late 1980s, but the park's focus shifted completely to the dry area in 1993, when it was purchased by Premier Parks and renamed Adventure World. Several steel roller coasters were added, among them the Python (originally half of the Lighting Loops) and Vekoma's first Mind Eraser. In 1998, a wooden twister coaster was added, Roar, designed by Great Coasters International.

The following year, the park became part of the Six Flags chain and took on the name Six Flags America (supposedly because it is just 20 minutes from Washington, D.C.). With that change came many others, including extensive remodeling and retheming - Looney Tunes characters became prominently featured in the kiddie area - and an entirely new section, Gotham City, was added (including a Skycoaster). Python was sent into storage, but three coasters opened that year: Two-Face: The Flip Side, Joker's Jinx, and Great Chase replaced Cannonball in the kiddie area. The 2000 season saw the addition of Superman: Ride of Steel, and in 2001 the Vekoma-designed Batwing opened.

The old water park is still around - now under the moniker Paradise Island - and is included with admission to the rest of the park, but is only open for a very small part of the May-October season.

Sources
http://coasternet.danimation.com/sfa.html
http://themeparks.about.com/library/weekly/blffawge.htm
http://www.americanmidway.com/reviews/sfa.html
http://www.sixflags.com/america/