How to Find All Vault Key Fragment in Borderlands 4

By Ambar Jimenez | 2025-09-14 12:48:24
The Borderlands franchise has always been synonymous with one thing: the hunt for legendary loot inside hidden Vaults. With the highly anticipated release of Borderlands 4, the looter-shooter experience has been taken to an entirely new level. This latest installment introduces a fresh mechanic for Vault discovery, challenging players to become true Vault Hunters by meticulously tracking down elusive Vault Fragments. These fragments are the key to unlocking the game's most powerful secrets, including unique gear and upgrades that can only be found by defeating the formidable Primordial Guardians.In this comprehensive guide, we'll delve deep into the mechanics of Vault Hunting in Borderlands 4, exploring how the new Silo system works and providing a detailed walkthrough for finding every Vault Fragment and unlocking each of the three main Primordial Vaults on the planet of Kairos.

Borderlands 4 Vault Hunting: Guide to Primordial Vaults

How the Vault Fragment System Works

Unlike previous titles, Borderlands 4 requires players to engage in a methodical, multi-step process to access each main Vault. The journey begins by "capturing" Silos scattered throughout a region. Kairos is divided into three major regions: The Fadefields, Terminus Range, and Carcadia Burn. Each of these regions contains a set of Silos that, once captured, provide a crucial hint about the location of a nearby Vault Fragment.Upon capturing a Silo, your map will display a large yellow circle indicating the general area where you need to search. As you enter this designated zone, a new Hot and Cold meter will appear on your heads-up display (HUD). This meter serves as a directional guide: the closer you get to the Vault Fragment, the more the meter's yellow bars will fill up. Think of it as a treasure hunt where your HUD acts as the divining rod, pulsing with more intensity as you near your goal.There are three Vault Fragments to collect in each region. Once you've successfully gathered all three, a new hint will appear on your map, this time pointing to the location of the Primordial Vault itself. The same Hot and Cold method is then used to pinpoint the exact entrance to the Vault.The journey doesn't end there. Inside each Vault, you'll face a series of challenges and a gauntlet of increasingly difficult enemies before confronting the region's ultimate boss: a Primordial Guardian. Defeating these powerful adversaries not only grants you access to unparalleled upgrades but also marks a significant milestone in your quest to uncover Kairos's deepest secrets.

The Fadefields: The Arch of Inceptus

The first major region you'll likely explore is The Fadefields. This desolate expanse holds the fragments needed to unlock The Arch of Inceptus, guarded by the formidable Primordial Guardian Inceptus. Finding these fragments requires a keen eye and a bit of exploration.

  • Vault Fragment 1: Located in the Coastal Bonescape, near the back of a building at Stillshore. This one is relatively easy to spot once you've captured the nearby Silo.
  • Vault Fragment 2: Found in a small opening in the cliffs north of The Launchpad, in an area known as The Howl. The Hot and Cold meter will guide you to this well-hidden spot.
  • Vault Fragment 3: This fragment is a bit trickier. It's hidden in the Idolator's Noose region, specifically at Rosemary's Reserve. To access it, you need to find a grate on the western side of thebuilding that can be opened, leading you to an underground passage.

Once all three fragments are in your possession, the location of The Arch of Inceptus will be revealed on your map. You'll find the entrance in the Dissected Plateau, perched on a tall mountain south of The Stubs. Be prepared for a challenging gauntlet as you make your way to the final boss, Primordial Guardian Inceptus.

The Terminus Range: The Arch of Origo

Next, your journey will take you to the perilous Terminus Range, home to the fragments for The Arch of Origo, and its guardian, Primordial Guardian Origo. This region presents new traversal challenges, including the use of glide lifts and grappling points.

  • Vault Fragment 1: Located in Cuspid Climb, take the glide lift from The Reliquary Silo north to a long, jutting cliff ledge where the fragment awaits.
  • Vault Fragment 2: Hidden in The Low Leys, you'll find a small opening in the cliffs southeast of The Pit. You'll need to climb and grapple up to an alcove to reach this fragment.
  • Vault Fragment 3: The final fragment in this region is found inside The Vestal Garrison building, located on the border of Windspear and Low Leys, specifically in a lower-level office room.

With the fragments secured, the path to The Arch of Origo becomes clear. The Vault Door is located in a cave behind the Augur Shrine, which can be found south of Checkpoint Taupe. After surviving the gauntlet, you'll face Primordial Guardian Origo, a boss who will test your skills and reward you with powerful loot.

The Carcadia Burn: The Arch of Radix

The final region is the scorching Carcadia Burn, which holds the last set of fragments and the final main Vault, The Arch of Radix. This area offers some of the most intricate environmental puzzles to solve.

  • Vault Fragment 1: This fragment is found in the Ruined Sumplands, northeast of Hull's Handbasket. It's a straightforward find once the Silo has pointed you in the right direction.
  • Vault Fragment 2: Located in Tonnage Peel, this fragment requires a bit of detective work. Look for an open cargo vessel west of The Wreck of the Last Great Hope that leads underground. You'll need to use your grappling hook to pullup a grate and then drop down to the lowest level to find the fragment.
  • Vault Fragment 3: This one is a simple find at The Dustbowl, northwest of The Tonnage Peel, near some broken-down machinery.

Once you have collected all three fragments from Carcadia Burn, the location of The Arch of Radix will be revealed. You'll find the Vault Door in an oasis located north of Stopflow Bowels. Here, you'll face the final boss in this series of quests, Primordial Guardian Radix. Defeating Radix is a true test of a Vault Hunter's might and will unlock the prestigious "Nothing Left to Guard"achievement/trophy, signifying the completion of your epic quest toconquer the Primordial Vaults of Kairos.

This guide provides the essential knowledge to navigate the challenges of Borderlands 4 and become the ultimate Vault Hunter. The new fragment and Silo system adds a rewarding layer of exploration and discovery to the core Borderlands experience, making the hunt for legendary loot more engaging than ever. Now go forth and conquer the Primordial Vaults! 🚀

Platform(s): PlayStation 5 PS5, Microsoft Windows PC, Nintendo Switch 2, Xbox Series X/S
Genre(s): First-person shooter, action role-playing
Developer(s): Gearbox Software
Publisher(s): 2K
Engine: Unreal Engine 5
Release date: September 12, 2025
Mode: Single-player, multiplayer
Video preview



Other Articles Related

How to Get a Vehicle in Borderlands 4
Learn how to unlockevery vehicle in Borderlands 4. Our guide covers finding Catch-A-Ridestations, vehicle types, upgrades, and customizations to dominatePandora and beyond.
How to Get Aegon's Dream in Borderlands 4
Unlock the secrets of Aegon's Dream in Borderlands 4. Our guide reveals thequest start location, step-by-step walkthrough, and powerful legendaryrewards for completing this epic mission.
How to Complete Electroshock Therapy Quest in Borderlands 4
Struggling with the Electroshock Therapy quest in Borderlands 4?Our guide covers how to find the conductor coils, power the transformer, and defeat the boss for epic loot.
What Are Lost Capsules in Borderlands 4
Uncover the mystery of Lost Capsules in Borderlands 4. Learn whatthese hidden caches are, where to find them, and the legendary loot they contain for daring Vault Hunters.
How to Respec Skills & Specializations in Borderlands 4
Discover how to respec skills and specializations in Borderlands 4.Unlock new strategies and enhance your gameplay with our guide.
How to Destroy the Jamming Device & Save Quent in Borderlands 4
Struggling with the jamming device in Borderlands 4? Our guideshows you exactly how to destroy it and save the fan-favorite character, Quent. Get the step-by-step walkthrough here.
All Difficulty Settings in Borderlands 4
Explore Borderlands 4's difficulty settings and understand how theyaffect your gaming experience. Choose the right level for thrilling  
How to Mute Claptrap in Borderlands 4
Unlock the coveted Kai Cenat skins in Fortnite with our guide.Explore strategies and tips to enhance your character's look andgameplay 
All Fadefields Vault Symbols in Borderlands 4
Unlock every secret. This guide reveals all Fadefields Vault Symbol locationsin Borderlands 4 for dedicated vault hunters seeking 100% completion.
How to Get Clearance for the Elevator in Borderlands 4
Navigate the challenges of Borderlands 4 with our guide on obtainingelevator clearance. Elevate your gameplay and explore new heights!
How To Trigger The Ecstasy of the End Quest in Silksong
Learn how to trigger the 'Ecstasy of the End' quest in HollowKnight: Silksong. Discover the key location, prerequisites, and steps to begin this mysterious mission.
How to Get the Flintslate in Silksong
Discover the steps to find thepowerful Flintslate in Hollow Knight: Silksong. Learn its location andhow to use this key tool to upgrade Hornet's weapons.
How to Drop Items in Borderlands 4
Learn the quick and easy steps to drop items for your friends in Borderlands4. Master the controls for PC, PlayStation, and Xbox to manage your loot effectively.
How to Get SDU Tokens in Borderlands 4
Learn the best strategies to earn SDU Tokens in Borderlands 4. Maximizeyour inventory space and elevate your gaming experience 
How to Get John Cena's Peacemaker Skin in Fortnite
Unlock John Cena's iconic Peacemaker skin in Fortnite! This guide covers allthe methods to get the outfit, from the Battle Pass to the Item Shop.Suit up and bring peace through superior firepower.