It's a book... of taverns. It has descriptions and NPCs for about a dozen different taverns. Each has about 2 to 4 pages of exposition, and some maps, and NPCs, and even magic items to boot.
Personally, my game did quite well with the tavern called "The Witch's Teat." It includes a fighting pit built around a Summon Monster spell that went wildly haywire. The little touches, such as the teleportation stones to keep monsters from getting out into the city? Nice.