But when I spoke to the manager, Joanne Mekis, and a bartender named Jack—who was busy behind the bar helping himself to shots—they told me that some of the finest blues musicians had come through the place. Moreover, the Mermaid served as the prototypical "nostalgic drinking establishment" in the documentary Music From the Inside Out, and the 1941 Rita Hayworth-James Cagney film Strawberry Blonde.

While the Mermaid fills up during its weekend concerts, weekdays can be slow. Tonight was no exception. In the corner of the bar, four middle-aged men sat hunched over their drinks. "That," Jack told me, "is the lawyer crowd. They come here to forget about the day and to just sit and listen to the music."

The music, on that particular night, was made by three elderly folks who had shown up with their guitars for the regularly scheduled open blues jam. They sat on a makeshift stage and jammed out tunes by Eric Clapton, Muddy Waters and Leadbelly.

"This place is no dive," says Jack. "It just refuses to change for anybody. It's been a bar since 1734. You can almost imagine Ben Franklin and his buddies stopping by here for a beer on their way west."