All that will be in the memorial. I don't think anything in the WTC before 9/11 is in its original location now. For a while a section of the underground concourse was preserved and integrated into the temporary PATH station, but its gone to make way for the new PATH station, and of course there's the survivor's staircase, now brought underground.
Peter-Citynoise.org
PS sorry for the off topic post.
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I have a question, in pictures for the tower's base, it appears a portion will sit outside of the bathtub. Will they just pile into the ground there, or will it be sort of like a cantilever over the sidewalk.