I started with the 9/11 museum (on its own page), then did the freedom tower, and then had some time left to walk around.
during my last trip, it was still being built
I then got in line for the new freedom tower, thankfully the line was not bad at all, I wsa up from outside in the street to viewing at the top in less than 30mn:
the elevator had a movie display of old times in NYC 'till present
I then had a bit of time left to burn (but not enough to go to the entrepid museum), so I walked towards chinatwon and little italy which happened to have a big ass celebration: