2-3 hours usually for almost most acts. And Depending on the your "seating" and who is performing you could guess when you should go. If they are real popular and you have GA go hours earlier. If you have a seat it's best for 2 hours - 30 minutes before.
Queen concert lasted 2 hours. Usually, seats are assigned when purchasing. We go half hour early, depending on the weather, because you have to wait outside for the doors to open.
It depends on the band but probably 3 or 4 hours
3 to 4 hours...30 mins early is koo
It depends on the individual act it various i would ask the united center directly.
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