I'm having a downtown wedding too. great views from aquarium but i didnt want to worry about outdoor/rain plans. Check out the Tremont Grand before you make any decisions.
We steered away from venues in Fell's Point because parking is a mess there.
We got married at the Science Center. The view from the lobby was great, you could do a tent upstairs on the roof too.
We've booked our wedding at the Maritime museum. It is smaller and more intimate, which works for us doing only about 100 people.
If you book the grounds for the ceremony, they will let you move everything inside on the day of if the weather doesn't cooperate.
Also, there is a parking lot right next to the museum you can either set something up in advance with if you think a lot of your guests will be driving.
The museum is definately worth looking into before you decide!
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