Part of the Radio Mast WTC 1
The 9/11 museum is full of poignancy and symbolism, the mast is from the top of one the towers. The tiles on the wall, almost 3000 of them, is the sky before the tragedy.  
The other feature of the museum is that there is a large area showing the people involved in the disaster where photography is not allowed. Good, not everything in life has to be photographed.
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