When Katy Mills opened in 1999, it sent a press kit out that had all sorts of useless trivia about the gargantuan size of the place, such as "Telephone wire: 2,600,000 feet, enough to go around Loop 610 13 times" and "The amount of dirt used to build the berm could fill 413,000 sandboxes." Only one fact is relevant to mall-walkers, though: The distance of the outer path in the mall, which comes full circle, is about one mile. Though Katy Mills doesn't open for shopping until 10 a.m. (and not until 11 a.m. on Sundays), it opens its doors to mall-walkers at 8 a.m. Once finished trotting through the brightly colored, Disneyfied mall, walkers can get their walking record filled out with how much they walked and how long it took at the information booth between Entrances Four and Five. In the past the mall has offered incentives, such as prizes like gift certificates and even Reebok shoes once they reach certain goals. Not bad, plus they don't have to deal with the Texas sun or heat strokes with all that air-conditioning (4,500 tons of air-conditioning units, enough to cool 1,324 homes).