The 13th Muse Pub

The 13th Muse Pub or The 13th Muse Tavern is a bar located somewhere in Rapture. It's actual location is currently unknown. There are two places it's name is seen at. The first is during the Neptune's Bounty loading screens. The second location is outside the northern window in the Proving Grounds. Seeing as how there is a screenshot of the bar during the loading screen, it can be speculated that the tavern is among the removed content.