Busch Gardens is probably our most internationally famous attraction, aside from the beaches. The park has extreme roller coasters, an area designed for small kids, shows, restaurants, lots of animals and seasonal events. Most people from the Bay area have been here, but if you haven't you should go. It's not as big as some of the other parks, but neither are the lines or the crowds.
The annual passes are really a great deal for anyone local. With a pass you get free parking and a discount on everything else at the park. For a few more dollars, you can add Adventure Island to your pass and you have your choice of two theme parks to attend for a full year.