Below the lowest residental areas of the city of Sharn (usually refered to as the “Depths”), the Cogs include ruins of older versions of the city, natural caverns, and some pockets of lava flow. These conditions are used to power the forges of industry, and a large amount of workers commute into its depths every day. It is also notable for the variety of monsters and extraplanar creatures that roam its secret passages.

The “civilized” parts of the Cogs (called the “Upper Cogs”) are divided into 3 districts:

• Ashblack
  • This western district is home to the Cannith forgehold.
• Blackbones
  • Slightly less polluted than the other districts (because of its eastern orientation), Blackbones is known for its significant warforged population, with their own warforged-specific tavern.
• Khyber’s Gate
  • Mostly filled with tenements, this district is filled with the dregs of society and races not accepted above ground, but is relatively peaceful because of a heavy Daask presence.

Depths and Sewers

• Above the Cogs but below the rest of Sharn are the Depths and Sewers. The sewers are the unmonitored parts of Sharn’s extensive water system, ruled by gangs of rats, goblins, and feral people. The Depths, or Undersharn, is the remnants of the dungeons and secret tunnels of Ju’Shaarat, sealed off by order of Galifar.