It is under the arena, yes. During games I believe it is $10 to park, and go down the street on either side, Agganis Way is one side, and I normally enter from Buick Street.
There's a lot under the arena. It has elevator and stair access to the venue. There's also a parking garage on Babcock St, on the same side of Comm Ave, short walk to the venue, as well as across the street at 121 Dummer St.
There is a large parking garage underneath.
It's either referring to the parking garage across the street, or there may be a garage in the rear of the facility.
I parked on the street when I came. I'm not sure where is the garage.
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