"Is it safe?" -Hero
"Safer." -RGBThe Pool of Tears is a location introduced in the first chapter, page 15, of The Property of Hate, where our protagonists rest for the night and are attacked by Fears the next morning. It was (presumably) named by RGB in Chapter 3, while talking with Madras.
Creatures that can be found here are Lies, Fears (although Fears are generally meant to be uncommon here), and The Butterfly. This was also the location that first introduced all three of these entities, since it was the first place our protagonists actually went outside of Manchester, and it was the Fears from here who gave Hero her Schism during their ambush.
The name "The Pool of Tears" also describes both a chapter title of, and a location from, Alice in Wonderland. This may have interesting repercussions for the world of the comic. Or, perhaps, it may simply be a shout-out, like the yellow traveling path or smokestack stairs.