Title: Diablo IV - Vessel of Hatred - Beast Graveyard Dungeon
Description:
The Beast Graveyard is located in the Field of Giants in Nahantu. The entrance is in the Beast Fate Wilderness.
You have to visit this dungeon for the "Deafened Mourning" sidequest. For this quest you have to collect the Iron Horn from a rhino inside the graveyard. This can easily be done simply by playing throug the dungeon. Afterwards you have to return to Wak'Lan and give him the horn.
I suggest finishing the dungeon by slaying Blackmailer, while you are there, though.
You can find him at the Rancid Point.
Link: https://www.digioso.org/d4_beast_graveyard