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This article is about the Sanctuary Caches. You may be looking for the Lost River Laboratory Cache or Alien Arch Caches.

Three Alien Caches serving as sanctuaries can be found located in a cave in the Deep Sparse Reef right next to the Sea Treader's Path Wreck (Wreck 7), deep within a cave in the Northern Blood Kelp Zone, and inside an impact crater left behind by a meteor in the Dunes. These three Caches each require one Purple Tablet to access.

Sanctuaries contain data hubs, atop which are Ion Cubes.

These data hubs contain the backed up consciousnesses of several members of the Precursor Race.

The Ion Cubes were placed in a purely ceremonial fashion but can be taken by the player to craft advanced technology or open Alien Arches.

Located within a small cave inside the Deep Sparse Reef, this Cache is sealed by a forcefield door that can only be opened with a Purple Tablet. At the far end of this Cache a data terminal can be found. Three data hubs can be found in both the left and right sides of the Cache, six Ion Cubes can be found on top of these.

A large wreck is just outside the cave entrance, across the biome border in the Sea Treader's Path. The wreck itself is edge-on to the cave.

Data Bank Entry[]

Alien Sanctuary Alpha[]

Architectural information has been downloading regarding this antechamber.

Ceiling Fixtures:
The structures mounted to the ceiling of the cavern cast a low green light over the data hubs below, but they are also regulating the pH level of the surrounding water, and emitting a low-frequency sound wave. It is possible the intent was to ensure ideal conditions for a practical end, but their purpose may also have been ceremonial, or even recreational in nature.

Ornate in design. The cubes mounted on the pedestals are not being drained of power, suggesting they served some more symbolic purpose. Similarities to old earth religious iconography may be coincidental, but they may also indicate some shared and ancient cultural history.


Located in a small cave, five hundred and sixty meters down in the Northern Blood Kelp Zone, this Cache is also sealed by a forcefield door that requires a Purple Tablet to open. This Cache features a data terminal in the center and four data hubs, two on either side of the terminal.

Data Bank Entry[]

Alien Sanctuary Beta[]

This antechamber consists of a series of data hubs, each adorned with an ion cube. These are networked up to the main terminal in parallel, presumably to ensure data integrity over time.

- Unprecedented data complexity
- Stored data was scanned into the system at the local terminal
- Original data source was organic in nature

Evidence suggests that this antechamber served as a sanctuary of last resort for the aliens that built it. In the event of catastrophe, they could retreat here and somehow transfer themselves to the data hubs for preservation.

It is unclear whether other members of the alien species ever returned here, or how many souls are backed up on the hubs, but the data stored is far too complex to reconstitute with the little information available.


This Cache is accessed through a meteor impact crater in the Dunes. The main chamber is reached through a long winded tunnel and is sealed by another forcefield door, which is also only accessed through a purple tablet. The tunnel continues into the main chamber, which contains four data hubs and one data terminal. Flora are also found scattered in the chamber, with occasional boulders on the ground and stalactites hanging from the ceiling. It is possible to take the Prawn Suit past the forcefield door, but the tunnel becomes too narrow to bring it any further; because of how long the tunnel is from the entrance, it is advised to leave a vehicle as close as possible for air resupply.

Data Bank Entry[]

Alien Biological History[]

This terminal contains data mapping the complete biological history of a member of the alien species.

The dataset is hugely complex, but some basic facts can be reconstructed.

Was grown from seed 1,708 earth years ago
Separated from broodlings early for special training
Inducted into temple of research as the youngest ever initiate, age 96
Downloaded a corrupted dataset and was stored for 3 years for refactoring
Relocated to the outer galaxy cluster to support disease research endeavors
Relocated to 4546B for high priority disease research
Contracted kharaa bacterium
Stored in Sanctuary 3, corporeal body safely disposed