Just so you know, Westminster Hall is not a church anymore. It's a hall that you can rent for weddings and events. We were only able to see it, because a nice gentlemen was preparing it for a wedding later in the day, and he let us peek inside. Nice, but not a site for tourists. The burying grounds are small, and you likely would need a tour guide to make it really interesting. Of course, the highlight is Edgar Allen Poe's grave (and possibly the monument at the entrance). If you are interested in US history, there are also some military figures associated with Baltimore there.
We weren't really impressed overall, having been to many cemeteries in our travels, but I must confess that our experience was a bit colored by the nature of the cemetery. Situated as it is in the middle of downtown, we had to be careful of the two men hiding in the cemetery behind the hall doing drugs. We also sidestepped the guy at the Poe monument who was taking the coins people left there. This was in the middle of the day, by the way. Urban and gritty has its place, but most cemetery aficionados aren't usually seeking that experience in the cemeteries themselves.
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