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Sizemore performing his usual services in the Cesspit.^Erf-b1-p013 From [http://www.erfworld.com/book-1-archive/?px=%2F053.jpg Page 53.

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The Cesspit is a location in Gobwin Knob. The Cesspit is full of crap, so it is here that Sizemore makes crap golems.^Erf-b1-p013

There may be other cesspits in other cities.

Speculation

It is not known exactly where the cesspit is located. In the one image of the Cesspit, it is open to the sky, which suggests it is in Courtyard, Outer Walls, or Tower, but not Airspace, Dungeon, or Tunnels.