Nuncio

Nuncio's statue. Art from SS.

Nuncio: where mailmen go when they get frustrated, bored, or ashamed of what they do. All lost or refused mail ends up here, and the mailmen try to deliver it. The statue in the middle changes, according to what culture is living there. The currency: dead rats.

At the back of the post office, a pit reaches several hundred feet down, seemingly without end. The post office workers avoid it. There is a large needle marked with Correspondence sigils at the bottom of the pit, which is so far down one can't even see the entrance.

Nuncio may have been made by the Bazaar, or something similar to it, to guarantee no message is undelivered or misunderstood. 

Fun fact: The basic idea for Nuncio was created by Spacemarine9, creator of the lore blogs Saint-Arthur and Saint-Beau.