Beneath the shimmering depths of Pharloom lies a hidden maze of pipes and decay known as the Putrified Ducts. This guide traces the precise routes, tools, and tricks you’ll need to reach this corroded underbelly and survive its foul secrets.
How to enter the Putrified Ducts through Memorium
To reach the Putrified Ducts through Memorium, travel to the lower section of the area where the echoing bells mark hidden passages. Strike the faintly glowing vines to reveal a crawlspace leading to a sealed chamber. Use the Resonant Needle ability near the memorial statue to activate the stone gate, then drop into the newly opened shaft. Keep an eye out for acid vents below; using the Hollow Shell charm will help you cross safely to the ducts’ entrance.
The first and most common way to reach the Putrified Ducts, is to jump through the narrow passage leading from the Choral Chambers into the Memorium region.
Sounds simple enough, but there’s a catch: You must use the Faydown Cloak‘s double jump ability to reach this passage.
If you decide to try this route, you must complete the following steps:
- Explore the Choral Chambers. Optionally, unlock the Grand Bellway Station and Grand Bellway Ventrica Station, as well as the Ventrica Station at the First Shrine (Songclave). This will make it easier to travel to the Memorium passage.
- At the bottom of the Choral Chambers, descend into Whiteward and the Underworks. At the heart of the Underworks region, get the Clawline ability. The Underworks also host various spool fragments and craftmetal locations, so it’s an important region to unlock anyway.
- Once you’ve got the Clawline, enter The Slab through the passage northwest of the Citadel Spa. Find the Bellway station in the lower area, and head west into Mount Fay (you don’t need to get kidnapped and dropped in The Slab region for this).
- Reach the top of Mount Fay, where you’ll receive the Faydown Cloak, thus unlocking the ability to double jump. You might want to pair this with the “Liquid Lacquer” quest, which is obtained in Bellhart after completing “My Missing Courier” and “The Great Taste of Pharloom,” and leads you to the top of Mount Fay as well.
Once you’ve jumped through the vertical passage into Memorium, break the ceiling to reach the larger chamber and take the second-lowest exit to the right. Keep going until you reach another large chamber and drop down. Enter the room with the wooden sign.
Inside this room, you might want to pay 70 rosaries to the machine to obtain the Memorium map. To continue your journey to the Putrified Ducts, jump towards the grey curtains on the ceiling to find a secret passage.
Drop down from the balcony, cross the bridge, and hit the breakable wall on the other side (which requires the double jump). Inside the room with the spikes, double jump again to reach the passage above you. This passage will lead you right into the Putrified Ducts.
How to enter the Putrified Ducts through Bilewater
The Putrified Ducts can be reached via the Memorium path in Hollow Knight: Silksong, with the alternative lower route opening from Bilewater after clearing the Memorium entrance. The Bilewater approach is more perilous, featuring tougher enemies and parkour challenges, so most players opt for the Memorium route for a smoother entry. To access the Bilewater entrance specifically, you’ll traverse from Sinner’s Road, break walls to create an ascent, then double-jump into a narrow upper passage that leads toward the final climb into the Putrified Ducts area; expect a maggot-filled swamp and environmental hazards along the way. For additional confirmation and routes, you can also consult video guides and wiki entries that outline the Memorium-to-Bilewater sequence and the required traversal techniques like double-jumping and wall-clinging.
Alternatively, you may enter the Putrified Ducts from the Bilewater region in the south.
Beware that the journey through Bilewater seems a lot harder than the one through the Memorium path (due to a multitude of enemies, tricky parkour, and an even trickier boss fight), so I recommend the latter. As it seems impossible to proceed through Bilewater without the Faydown Cloak‘s double jump, the preparation phase for both routes is the same.
If you still prefer to enter the Putrified Ducts through Bilewater, here’s what to do:
- Enter the Sinner’s Road region above Greymoor.
- Walk east until you reach the bench sign in the vertical chamber, where you might want to rest. Beware that the bench is broken, but you can fix it by breaking the wall above the bench (left side) and completing a brief parkour run.
- Leave the vertical chamber through the ceiling and head east. Destroy this wall to enter Bilewater:
- Go right until you find the massive vertical chamber. On the left side of this chamber, use double jump to enter the narrow passage.
- Parkour your way up, then take the upper road to the east when you can go no further. Follow the path as it loops back to the upper left, where you’ll find the Groal The Great boss (whom you also need to defeat to reach Act 3).
- Defeat him, leave the boss arena to the left, and jump up to enter the Putrified Ducts.
Where to find the Putrified Ducts map location
The Putrified Ducts map in Hollow Knight: Silksong is located just south of the area’s first bench, accessible after entering from the Memorium route.
Path from Entrance
From the Putrified Ducts entrance (via the spike tunnel from Memorium), drop down carefully through the maggot-infested swamp platforms while moving right. Proceed past enemies to reach a door; enter the next section, then head down and left along the lower pathway, avoiding vines and ranged foes.
Map Pickup Spot
Attack a retractable vine platform to ride it upward; at the top, interact with the nearby table to grab the free map (no rosaries needed). This reveals the full layout, including hidden paths and collectibles like the Key of Apostate further below.
How to get from Memorium to the Putrified Ducts entrance
From the Memorium bench, head right to the final room where progress seems blocked.
Hidden Ceiling Access
Double jump into the narrow gap in the ceiling to reveal a secret rooftop passage. Run across the rooftop to the dead end on the far right.
Breaking into Ducts
Double jump up to strike and shatter the breakable wall ahead, opening the spiked tunnel entrance. Use Clawline on walls and double jump through spikes to drop directly into Putrified Ducts’ main vertical chamber.
