Weeping Quarry is a Saronite mine used by the Scourge. It is located to the south of the Shadow Vault.
There is a kind of maw at the bottom of the water in the center of the quarry which moves and seems to be alive. Perhaps one of the "thousand maws" of the Old God Yogg-Saron or a different Old God. It looks similiar to and shares the model with C'Thun.[1] It is possible to swim into the mouth and past it. The mouth seems to disappear with only the corners remaining.