To do everything at KSC really requires 2 or 3 days. To see the majority of the good stuff will take about a day. There are 3 different tours, that are not part of the general admission. 1 goes to the firing rooms attached to the VAB, 1 goes out to Cape Canaveral, where the early rockets were launched, and the other goes out to LC 39, where the shuttles took off, closer to a lot of the other bldgs. that you only see from a distance, like the checkout bldg., where they would assemble pieces of the ISS, the crew compartments of Apollo, and where the astronauts stay when there here in Fl. The problem is that the length of the tours, and the timing, makes it impossible to see all of the special tours in 1 day. The general bus tour, can take anywhere from 2-3 hours, and is self guided and paced. You could easily spend several hours alone in the Saturn 5 bldg. alone because of all of the exhibits and side shows. The Visitors Center can take several more hours also, with all of the exhibits there.