Dwarves of Rockwater
From the introduction:
The adventurer levels vary greatly depending on how the adventure is run. If the characters are generally smart, cautious, and do not feel as though they have to kill everything (they are able to choose their battles wisely) then they can be as low as levels 3-6. If the DM makes it difficult for them to avoid confrontations, or they are suicidal, they need to be at least level 10 to survive this adventure.
This is a dungeon crawl. There is no plot that comes with the actual adventure. I used it for a quest to ask for aid in a time of war from the dwarves. You can make up your own story behind it.
User summary:
The maps used in the scenario are derived from B4: The Lost City; the needed sections are reproduced in this document.