Bloodborne - Trophy Guide - The Source of the Dream, Find the Abandoned Old Workshop.

To unlock this Bloodborne trophy you will need to find the Abandoned Old Workshop.

Bloodborne (Abandoned Old Workshop) The Source of the Dream Trophy Guide
Abandoned Old Workshop is a secret (optional) area well hidden in the Cathedral Ward section that looks exact the same as Hunter’s Dream, only it’s real. You can get several items that are nowhere to be found in the game elsewhere. You will also find a One Third Of Umbilical Cord here that you will need if you want to experience the third (secret) ending.

There is one prerequisite before you can access the The Abandoned Workshop, which is that you have to kill the "Blood-Starved Beast" boss.
This will unlock the door to right of the Cathedral Ward lamp (walk down the first set of stairs first) that will open a new area for you.
Visit Gehrman in the Hunter's Dream first if the right door is still locked, teleport back to the Cathedral Ward lamp and go through the right door of the building and up the elevator.

When you leave the elevator take the exit to the left and cross the bridge (watch our for some enemies here, one is shooting from upstairs).
Do not enter the building and run around it to the right and drop down the ledge , follow this path you will enter a room and end up on a wooden platform.
As soon as you come into this room, just walk onto the bridge and turn left. You will see a single little board sticking out, next to the top of some ropes that hang down below it.
Walk towards the ropes from the edge of the bridge and you'll drop on a platform, use your blood vials and fall down again to a platform with a big door which is the door platform.

Open the door, go down the stairs and you will enter Abandoned Old Workshop area, the trophy will pop up. Congratulations you have unlocked this trophy!

You have found the Abandoned Old Workshop! Congrats!

Abandoned Old Workshop Walkthrough

You can find some unique items in this area and if your dream was to run around in Yharnam with the Doll Set...this is your chance!
The Doll Set can be found in a chest where the Bath Messengers are in the Hunter's Dream.
Run up the stairs and inside the building and you will find One Third of Umbilical Cord on the Memory Altar. You will also find the Small Hair Ornament in the cabinet in the middle of the room.
Go outside the back entrance of the building (look to your left) you will find a Old Hunter Bone in front of a grave (tombstone) where the Insight Messenger Shop in the Hunter's Dream.

There is nothing else to do here so after you have explored it , light the lamp in the building (if you haven't done so) and continue your journey in Yharnam.