Yes they have a elevator not sure about handicap parking
Parking is rather difficult at this location but they have assisted elevator service to get to the concert hall. That's a big plus. I've gone over an hour early and wasn't able to get Parking in front of the facility and this is the first I've even heard about Parking in the back. It would be a bit of rise as noted in the previous post. My suggestion is if you are traveling with someone to get dropped off in front then wait for your party or meet them at your seat.
There are handicap spots available on Station Place, the road behind the hall. It will still be a bit of walk unless you manage to get parking on the street in front of the building. There is an elevator to get into the music hall, however if you have seats in the mezzanine balcony there isn't an elevator that goes up that far. So hall seats are the way to go if you have trouble with stairs.
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