Continue down the path away from the stairs and between the buildings. There's a Retainer inaccessible behind large chunks of ice in an alcove to your left and some items also inaccessible in an alcove to your right. Note them, but ignore them for now.
In the clearing ahead with the frozen fountain, there are three Sorcerers and a Crystal Sorcerer. They'll be more than happy to gang up on you, but you can use the geography to your advantage.
Walk to your right and stop behind the first barrier made of ice. Creep out to the right of the ice and attract the attention of the two Sorcerers. They'll charge. Stay behind the ice to defend against attacks from the Crystal Sorcerer in the distance.
When they're dead, walk behind the ice barrier in front of and to the left of the frozen fountain. Creep out, defenses up, wary of the enemy between the arched pathway, who will fire projectiles. Turn left and lure the Sorcerer toward you and behind the ice barrier, where you can fight him in relative safety.
Underneath the archway is a Crystal Sorcerer of Eleum Loyce, a powerful variant of the regular Sorcerers. He's aggressive and has more health than his compadres, so prepare for a tough fight.
Once he's down, head through the archway, and you'll attract the attention of two more enemies: a Crystal Sorcerer with a spear and a shield hiding in an alcove to your left and a Sorcerer with a sword hiding further down on you right. When they begin charging, double back to the area near the fountain. Use the ice barriers to create as much separation between the two as you can, and do your best to take them out one at a time.
When they're dead, walk through the archway again, turn left, enter the doorway and pillage a corpse for Small Blue Burr x 5, an item that temporarily boosts magic defense.
Continue down the path, around the snow bank, and turn left toward the building. A Sorcerer is standing above you, and he'll begin firing his magic your way. If you have ranged weapons, you can lock onto and kill him from a distance. If you don't, turn left, run up the stairs to his left and, at the top, charge toward and kill the Crystal Sorcerer in front of you. Turn around, and kill the Sorcerer who was standing above you earlier.
Enter the foggy door next to where the Sorcerer was standing, ascend the steps and walk around the crates to get the attention of the three Sorcerers and the Frozen Dog in the room. Back down the stairs to create separation between the enemies and take them down one at a time.
When they're dead, open the door on same wall as the staircase you used to enter the room. Kill the Crystal Sorcerer on the next staircase and make your way up, though the next room and up another staircase.
Here on the roof, you'll see three treasure chests encased in ice. In front of the middle one, a Crystal Golem will arise from the floor. Block his powerful melee attacks and backstab whenever possible.
With the treasure chests at your back, head to the far left corner of the rooftop. Drop down, drop down again and pillage the corpse for Monastery Charm x 3, an item that cures poison and restores HP.
Continue down the path, keeping the building on your right, and pillage another corpse sitting near a tree and a Retainer for Dark Clutch Ring x 1, which increases your Dark attack and protects you from Dark attacks.
Continue up the hill past the tree, hop down, and you'll find yourself just outside the entrance to the building. Head back up and open the door on the other side of the first room past the first staircase.
There are two enemies you have to worry about here. Ascend the short staircase far enough to convince the Crystal Sorcerer to charge you. Back down in safety from the spells that the other Crystal Sorcerer in the distance is throwing and kill the first. Keep your shield up and close the distance between you and the second Crystal Sorcerer. Kill him and enter the doorway on the opposite side of the area where he was standing.
Kill the Hollow, smash the crates and follow the winding path ahead. Kill a Crystal Golem. Continue forward, kill another Crystal Golem, who's pretending to be sleeping just beyond where the path bends right. Make sure to get in a hit before he wakes up.
At the end of the path, pillage a corpse for the Old Bell Helm, which is a helm that looks ... well, like a bell.
Retrace your steps back to where you killed the Crystal Golem between two doors. Instead of going through the other door, follow the path to its left, if you're facing it. It dead ends in an area with four unlit fire goblets. You can't do anything here right now, but keep it in mind for later.
Head back, enter the door, and drop though the floor. Light the Abandoned Dwelling bonfire.
Check out the gallery below for an overview of the corpses to pillage and the items to collect in this section.