You will be able to buy your tickets at the kiosk when you arrive
I'm not sure, I purchased my tickets thru CityPass
We purchased them there for the 8:30 p.m last night
The ledge is open for up to 3 people at a time not sure about online because I purchased mine at the kiosk
It should show as available (if you are trying to get general addmition) 4 pm, 5 pm, etc
Not sure but I'd go ahead and call to find out what's going on. As I stated, the ledge was closed during our visit and I hear there are better 360° views than the Willis Tower.
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