For those who need an even bigger WTC fix, PBS’s long-running science program NOVA has a detailed, hour-long program on the engineering of the site, including an in-depth look at the materials used on site, as well as lengthy interviews with the architects, engineers, and contractors working on the colossal project. Thanks to unparalleled access granted by the Port Authority, NOVA gathered footage for the episode over a five year period, so expect lots of dramatic time lapse video.