The 5th has a partnership with about 4 lots near them. If you buy a parking pass with your tickets, it's really the best and easiest deal. I park at the garage on 6th next to the WAC garage.
That same garage, in the City Center building, also has an entrance on Union St., between 6th and 5th.
FYI: if needed, you can drop people off on 5th right at the theater entrance. Another option is to use Uber and they can drop off and pick up at the entrance. The garage on 6th is close; just get there early.
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