All Vault Key Fragment Locations in Borderlands 4

The sprawling world of Kairos in Borderlands 4 is filled with secrets to uncover and powerful loot to acquire. Among the most rewarding endgame activities are the Primordial Vaults, challenging arenas that offer exclusive rewards. But before you can claim the treasures within, you must first prove your worth by assembling a key for each vault. This requires hunting down three hidden fragments scattered across each of the planet’s major zones.

This guide will show you where to find vault key fragments in Borderlands 4, providing detailed maps and instructions for every fragment in The Fadefields, Carcadia Burn, and Terminus Range.

How to Find Vault Key Fragments

Each of the three main zones on Kairos—The Fadefields, Carcadia Burn, and Terminus Range—contains one Primordial Vault and three corresponding key fragments. While you can stumble upon these fragments through pure exploration, there is a more systematic approach.

Throughout each zone, you will discover Order SILOs. Hacking the console at these SILOs will not only unlock a new fast travel point and reward you with SDU Credits but also mark a large search area on your map for a nearby fragment. Your ECHO-4 device will then act as a scanner, indicating your proximity to the fragment as you get closer.

While hacking SILOs is helpful, it isn’t required. You can use this guide to go directly to each fragment’s location and speed up the collection process.

The Fadefields Vault Key Fragment Locations

The first set of fragments can be found in the arid, rocky landscape of The Fadefields. You will need to find all three to open the vault located in The Stubs.

1. Coastal Bonescape Fragment

• Location: Stillshore, Coastal Bonescape

This fragment is located in the southwestern corner of the Coastal Bonescape region, within the Stillshore point of interest. After unlocking the Stockroom SILO or fast-traveling nearby, head west toward the shoreline. You will find the Vault Key Fragment sitting on a wooden box just outside one of the dilapidated houses, near a tower with a slow-spinning fan.

2. The Howl Fragment

• Location: Cave Overhang, The Howl

Located in The Howl region, this fragment is tucked away inside a cave with a large, noticeable entrance. It’s positioned north-northeast of The Launchpad landmark. The easiest way to approach is from the north side of the cave system. The fragment rests on a ledge inside, nestled into the stone structure.

3. Idolator’s Noose Fragment

• Location: Rosemary’s Reserve, Idolator’s Noose

You can find this fragment within the Dissected Plateau area, specifically inside the Rosemary’s Reserve point of interest in Idolator’s Noose. Look for a grapple-able vent on a wall southeast of the main Propaganda Tower. Pull the vent open to reveal a hidden room. The Vault Key Fragment is inside, sitting in a corner under some red lighting.

Carcadia Burn Vault Key Fragment Locations

The fiery, industrial wasteland of Carcadia Burn hides the next set of three fragments. Collecting them will grant you access to the vault hidden beneath a broken bridge in the Grindstone of the Worthy.

1. Lopside Fragment

• Location: One Pumper Gas Station, Lopside

This fragment is found in the Lopside region, south of the Makeshift Chalet safehouse. Follow the main road until you spot a rundown gas station with a “One Pumper” sign. On the side of the building, you will see a grapple node. Grapple up to the second-story open-air floor, where you’ll find the Vault Key Fragment resting on a long dining table.

2. Ruined Sumplands Fragment

• Location: Hull’s Handbasket, Ruined Sumplands

Head to the northwest area of the Ruined Sumplands. The fragment is located near the water’s edge, just northeast of the Hull’s Handbasket point of interest. To find it, go to the left of the large bridge that leads north and head down the hill toward the water. The fragment will be sitting on the ground near the shoreline.

3. Tonnage Peel Fragment

• Location: Wreck of the Last Great Hope, Tonnage Peel

This fragment is hidden deep within the massive shipwreck that dominates the Tonnage Peel region. The entrance to the correct path is not obvious from the map marker. You need to get underneath the southeast portion of the ship. Follow the road that runs alongside the wreck and find an entrance on the ship’s southwest-facing wall. Proceed through the passage until you find a vent on the floor marked by a blinking red light. Grapple the vent open, drop down, and follow the short path to find the Vault Key Fragment.

Terminus Range Vault Key Fragment Locations

The final set of fragments is scattered across the frozen peaks and treacherous valleys of the Terminus Range. Finding these will unlock the last and most well-hidden Primordial Vault.

1. Cuspid Climb Fragment

• Location: Hidden Cave, Cuspid Climb

This fragment is located near the center of the Cuspid Climb region. It’s highly recommended to unlock The Reliquary SILO first, as you will need to use its communications balloon grapple point to reach the fragment’s location. Before grappling, look north toward a large rock bridge near a waterfall. Glide over and land near the cave entrance there. Head inside, climb up to a small ledge where two bodies are, and you will find the Vault Key Fragment on the floor.

2. The Low Leys Fragment

• Location: The Pit, The Low Leys

Found near The Pit point of interest, this fragment requires a bit of climbing. From the road leading north toward The Pit, stop near a large dead tree. From here, look northeast for a series of rocks you can climb. Ascend the rocks to a platform where you’ll find a grapple node. Grapple further up the mountain to a higher ledge where the Vault Key Fragment is waiting.

3. Windspear Fragment

• Location: The Vestal Garrison, Windspear/The Low Leys border

This fragment is found inside an Order base, The Vestal Garrison, located on the border between the Windspear and The Low Leys regions. Enter the base from its southern side (in The Low Leys) and clear out the Order enemies. Go inside the main building and head to the second-floor office area with computer monitors. The final Vault Key Fragment is resting on a crate below one of the large screens.

Once you have collected all nine fragments, you will have unlocked all three Primordial Vaults, giving you access to some of the most challenging fights and rewarding loot in Borderlands 4.