Anor Londo, which is culturally significant in the world of Dark Souls, is basically just a large cathedral (which featured in a boss fight in the first Dark Souls and is now abandoned and dilapidated) and there are no lights on inside.This guide will point you to the bonfires and shortcuts in the area, as well as key items you can pick up, and where to find the boss fight.
Anor Londo bonfire in Dark Souls 3
Getting to Anor Londo from Irithyll is a trek, but isn't difficult to work out. From Pontiff Sulyvahn's bonfire go out through the back of the church and across the courtyard (either through the Deacons casting fireballs or the sleeping giants) into the opposite doorway, and then up using the roof walkways until you get to the side of the building where all the silver knights are standing firing arrows at you. Run past them to the left and find another roof leading down, then swing right and go into an enclosed circular room. The exit is on your left as you walk in. Immediately to the right of the exit is a lever, which brings down an entire spiralling tower for you to step on. Run to the top of it and push the mechanism in the middle around to make the tower go up again, taking you up to Anor Londo and your first bonfire.
Prison Tower bonfire in Dark Souls 3
From the Anor London bonfire turn around so you're facing the moving tower that you just came up on, and run back down the spiral until you reach the bottom, where the platform you walked in on should now be jutting out into nowhere, towards the top of a church tower. This has actually connected to an invisible walkway (so the messages left on the floor by other players are telling the truth, for once). If you walk forwards in a straight line you'll be able to reach the tower and drop onto it, where there's a bonfire for you.
This tower is the prison of Company Captain Yorshka, who is the leader of the Darkmoon Covenant. She's sitting quietly on the outside of the tower. If you go into the tower and look down then you'll see you can drop down using the rafters, which takes you back to the Church of Yorskha bonfire in Irithyll. Ah, Yorshka. That makes sense.
Aldrich, Devourer of Gods bonfire in Dark Souls 3
Appears after you defeat the boss Aldrich, Devourer of Gods (who is just a treasure, as you can imagine).
Shortcuts at Anor Londo in Dark Souls 3
It's a small area, so there's only one, and it's a bit of a drag opening it, but will help you out in the future. Starting at the Anor Londo bonfire run up the stairs and left at the top, because the doors are obviously locked so don't even try them. As you carry on around to the left you'll see a doorway, which you can go in to find the body of a giant as well as some narrow stairs. Keep heading up - you'll cross briefly outside and back into the cathedral again, which is incredibly dark because it's abandoned. As you step inside the front doors of the cathedral are on your right, and the back, with the boss fog wall you know and love, is on your left.
From where you are you can take stairs up to your right, which will lead you around the front of the cathedral on a platform, giving you a good look at the room, or take them down to your left, which will run you into a group of deacons chucking fireballs. The shortcut will open the front doors of the cathedral, but there's a gurning spider/monkey monster in front of them. He jumps around a lot, but a hit to the face will stagger him and do a lot of damage. To the right of the doors is the mechanism to open them. Hurrah!
Key items at Anor Londo in Dark Souls 3
Run up the stairs from the Anor Londo bonfire and left, into the stairwell with the dead giant. His body is what you loot the coal from, although judging by the placement of the item orb he was keeping the coal somewhere on or about his head, which was weird of him. Anyway, grab the coal to give to Andre the Blacksmith and unlock some new weapon upgrade options.
Stand in front of the doors of the Cathedral and face into the main hall. Hug the the left wall for a chest (carefully; we know it's dark). This holds the Estus Shard, which you can use to increase the uses on your Estus flask.
Sun Princess Ring
We don't usually point out all the jewellery and other gear you can pick up, because finding them yourself is part of the wonder of the game, but this ring is great - it gradually restores your health over time - and it's easy to miss after you kill Aldrich, because you have to catch a ride up on one of the lifts at the back of his boss area, and if Aldrich is the third Lord of Cinder you take out you'll be teleported out of there in a cutscene as soon as he dies (but you can use the bonfires to get back there; the one for his area will become active automatically if you get teleported away). So, from Aldrich's bonfire go to the back of his boss arena and wait for one of the timed lifts that are either side of the statues at the back, and go up into an empty area that seems to have been some kind of bedroom for a giant. The ring is in front of a massive chaise longue.
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