It was on Broad Street, where Folio is now, I believe. The imitation moved around the corner on to Franklin. For what it is worth, the reincarnated "Littlest Bar" bar, no longer so little, is now just down the way on Broad.
There used to be a crazy sounding lesbian bar late 70's early 80's just around the corner on Franklin too. I remember trying to sneak in one night because I could hear a killer live band from out on the street. But the bouncers told me I didn't fit the bill. It later went out of business when a fire broke out in the bathhouse located on the upper floors. Some investors who own a chain of strip clubs turned the property into a popular Italian restaurant. The restaurant is gone, but Centerfolds Boston, Centerfolds 2000 Oxford, Centerfolds Worcester, etc. live on in their respective communities.