The Speakeasy bar mentioned above reminds me of Lincolns, in Portland, Maine.
https://www.facebook.com/LincolnsPortlandMaine/about
It's not known for high-end liquor; it's called Lincolns because all drinks (beer, wine, liquor) are $5, cash only. It's also meant to replicate a speakeasy; once inside the decor is comfy old-timey. And they don't publish an address, though you can find it elsewhere on the web. No outside signage of any kind. There is an unmarked stairway leading down to a room with no obvious exit. Before my visit I'd read that the door into the bar was behind a swinging bookcase in that room, but when I was there that wasn't how it worked; the room had been completely reworked and the door had been hidden differently. It was a fun visit.