10am but I went by recently and it appeared closed. I'd call about COVID hours if you want to tour the building. Otherwise the view from the top is great.
Do you have to have tickets?
Was there at 5:30a the other day with no issues.
There was no real opening per se when I checked it out about three or four weeks ago. You can go up the exterior steps as long as the park overall is open, see the view but not go in the structure. A guy was playing jazz, it was sort of nice. It's not worth a trip in and of itself, but a nice enough diversion.
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