Archaeological site
Version

This article is for the PC version of Stellaris only.
Throughout the galaxy are scattered Archaeological Sites, areas where remains of ancient civilizations have been preserved relatively intact. They can be discovered while surveying, generated at game start, or uncovered a few years after a planet is colonized.
Mechanics[edit | edit source]
Most archaeological sites are revealed by surveying, with a 1.23% chance of creating a site, if the celestial body can support one. If a site is created this way, the chance is reduced to 0.25% for 5 years. Unlike anomalies, each time a celestial body is surveyed, a archaeological site can be created. Some archaeological sites are specifically created by anomalies, origins, special projects, other archaeological sites, or events. Most archaeological sites are visible to all empires once discovered, while a few are visible only to the discovering empire. The presence of an archaeological site is visible both in the system and galaxy view with this icon: . If a system contains more than one archaeological site, clicking the icon on the galaxy view will cycle through the sites.
An archaeological site can have 1-6 Chapters in addition to an introduction chapter. Each chapter has its own narrative and rewards and has to be unlocked before it becomes visible. Chapters are unlocked via Excavation. As long as an archaeological site is within an empire's borders, that empire can task a Science Ship with an assigned scientist to excavate the site. Excavation proceeds in phases, each taking 90 days. This time is affected by the following:
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Modifier |
---|---|
![]() ![]() |
+25% |
![]() |
+10% |
![]() |
−30% |
Regular AI empires | −50% |
At the end of each phase, a die is rolled, resulting in a random number from 1 to 10; adding the current number of clues and the Scientist's archaeology skill (see table below) and subtracting the chapter's difficulty gives the total result, as in the following formula:
.Archaeology Skill Source | Bonus |
---|---|
Per ![]() |
+1 |
![]() |
+1 |
![]() |
+2 |
![]() ![]() |
+2 |
A result of 14 or greater completes the current chapter; a result of 11-13 adds 2 clues for the next phase, a result of 6-10 adds 1 clue, a result of 5 or less adds no clues and can trigger various events, depending on the archaeological site and chapter.
Excavation can be paused and resumed at any time with no penalty. If the system with the archaeological site is gained by another empire, that empire can continue the excavation from the current chapter, but does not gain any rewards from already completed chapters.
Many chapter rewards are a number of minor artifacts; as these are only available with the
Ancient Relics DLC, sites which do not require that DLC may have an alternate reward or no reward for chapter without it.
Base game sites[edit | edit source]
The following sites do not require any DLC to be enabled.
Site | Chapter rewards | Requirements |
---|---|---|
Ancient Battle Site![]() |
|
Uninhabitable planet |
Strange Asteroid![]() |
|
![]() |
City of Bones![]() |
|
![]() |
Frozen Complex![]() |
|
![]() |
Mutant Fossils![]() |
|
![]() |
Ruins![]() |
|
Uninhabitable planet |
Subterranean Hollows![]() |
|
Habitable planet |
The Endless Expanse![]() |
![]() | |
Ix Belèn![]() |
|
![]() |
Seeds of Destruction![]() |
|
Crash Site anomaly outcome |
Message in the Canopy![]() |
|
Message in the Canopy colony event |
Message in a Bottle![]() |
|
On Solar Sails Anomaly |
Unique systems sites[edit | edit source]
The following sites can only be found in certain unique systems
Site | Chapter rewards | System |
---|---|---|
Ancient Robot World![]() |
|
Ultima Vigilis |
The Crashed Ship![]() |
|
Zevox |
Desiccated![]() |
|
Orvall |
Never Forget![]() |
Hauer | |
One Last Hope![]() |
Polaris | |
Debris Belt![]() |
|
Odryskia |
Tiyanki Grave Mound![]() |
|
Tiyun Ort |
Ruined Star System![]() |
|
Shallash |
The Signal![]() |
Larionessi Refuge |
Origin Sites[edit | edit source]
The following archaeological sites are generated by Origins.
From Gateway Sent[edit | edit source]
The From Gateway Sent archaeological site is discovered by investigating the special project created by the Galactic Doorstep origin.
Site | Chapter rewards |
---|---|
From Gateway Sent![]() |
On the Shoulders of Giants sites[edit | edit source]
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Available only with the Federations DLC enabled. |
The On the Shoulders of Giants origin adds a lengthy archaeological site chain in the empire home system. The narration of the last two chapters of the final site is random, but the rewards are always the same.
Site | Chapter rewards |
---|---|
Ex Gravitas![]() |
|
Something Waiting![]() |
|
Buried Deep![]() |
|
In Memoriam![]() |
|
The Last Stand![]() |
|
Dark Secret![]() |
|
Benign Cover-Up![]() |
|
Bury The Hatchet![]() |
|
Quantum Catapult[edit | edit source]
![]() |
Available only with the Overlord DLC enabled. |
The Slingshot to the Stars origin adds an archaeological site in the pulsar system where the ruined Quantum Catapult is located.
Site | Chapter rewards |
---|---|
Quantum Catapult![]() |
Ancient Relics sites[edit | edit source]
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Available only with the Ancient Relics DLC enabled. |
The Ancient Relics DLC adds a large number of archaeological sites to the game.
Site | Chapter rewards | Requirements |
---|---|---|
Relic Rails![]() |
![]() | |
Ruined World![]() |
|
Omni System |
Asteroid Blast Door![]() |
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Fossilized Remains![]() |
|
Fossils Discovered colony event |
Ancient Tomb![]() |
|
|
Moon Base![]() |
Shielded Relic system | |
Abandoned Ecumenopolis![]() |
|
Finishing the Moon Base dig site |
Gas Giant Structure![]() |
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Robot Debris![]() |
![]() | |
Crashed Starship![]() |
Uninhabitable planet | |
Moon Bump![]() |
|
Uninhabitable planet |
The Echoes Inside![]() |
![]() | |
Target from Orbit![]() |
Uninhabitable planet | |
Hole in the Ground![]() |
Uninhabitable planet | |
Too Angled![]() |
Uninhabitable planet | |
Déjà Vu Dig![]() |
Uninhabitable planet | |
Trench World![]() |
|
![]() |
Any Other Rock![]() |
|
![]() |
Beautiful Bubble![]() |
|
Uninhabitable planet |
Get Inside![]() |
Uninhabitable planet | |
Anyone Home?![]() |
Uninhabitable planet | |
The Grand Herald![]() |
![]() ![]() ![]() ![]() | |
Beneath the Waves![]() |
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Get to the Bottom![]() |
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Dotted Archipelago![]() |
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Popular Rock![]() |
|
![]() |
Strange Flows![]() |
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Message in the Dust![]() |
|
![]() ![]() ![]() ![]() |
Whispers in the Stone![]() |
|
![]() |
Kleptomaniac Rats![]() |
|
Rubricator System spawned in by the Weapon Trails Anomaly |
Hidden Worlds![]() |
|
5% chance to trigger on clearing one of the following ![]() |
The Library![]() |
|
![]() |
Ruined Station![]() |
|
Neutron Star or Pulsar |
Weapons Cache![]() |
Terraforming Event |
Precursor sites[edit | edit source]
Precursor Archaeology Sites are visible only to the empire that starts the event chain and are used to advance the Baol and Zroni event chains. When a Zroni Archaeology Site is discovered, the planet also gains a deposit of 2-4 Zro.
The Sentinels[edit | edit source]
The Sentinels is an Archaeology Site with slightly different mechanics. It can be discovered after a planet is colonized and adds an archaeological site blocker to the colony.
Site | Requirements |
---|---|
The Sentinels![]() Adds an ![]() |
![]() ![]() 5% chance to trigger by clearing one of the following ![]() |
Chapter | Effects |
Chapter 1 | |
Chapter 2 | |
Chapter 3 |
Always an Option:
|
If any of the outcomes comes to having the 9 Sentinel armies attacking the colony totaling 2350 garrison/army power here are the outcomes of the battle:
- The Sentinels win and seize control of the colony
- The sentinels start purging owners pops
- The planet can be retaken and liberated from the Sentinels (see Sentinels defeated)
- If the pops get liberated before they get fully purged they revive a liberated 30%
happiness boost for 10 years
- If the pops are left to be fully purged, the colony gets destroyed and the last pop will escape to a randomly owned planet. Reveals and enables the "Into the Earth" special project above the Sentinel planet. Choice of:
- Put their minds to work with some science: Receive the
Ever More Science planet modifier on your Capital +10%
- Modify the Evermore to entertain the masses: Receive the
Ever More Joy planet modifier on your Capital −10%
+5%
- Put their minds to work with some science: Receive the
- The Sentinels are defeated (liberation also applys for this)
- Gain the
Sentinels metal feature on the colony
- Defeating the Sentinels also reveals a tomb entrance and a Choice between:
- Investigate the entrance Issues special project "Into the Earth". Once completed chose between:
- Purge and repurpose: gain
300 Influence
Cheap Thrills planet modifier −10%
+5%
- Virtual hunting ground: If
or
gain:
300 Influence
Cheap Thrills Evil planet modifier +10%
+10%
−10%
+5%
- Replicate the technology: If
and
gain:
- Issue the "Replicate the Evermore" special project. gain the
Cheap Thrills EMPIRE modifier −10%
+5%
- Issue the "Replicate the Evermore" special project. gain the
- Lab rats:
- Gain the
The Evermore planet modifier +10%
- Gain the
- Purge and repurpose: gain
- Seal the entrance
- Investigate the entrance Issues special project "Into the Earth". Once completed chose between:
- Gain the
Other Expansion Sites[edit | edit source]
Certain archaeological sites require other DLC to be enabled.
The Broken Gates[edit | edit source]
![]() |
Available only with the Leviathans DLC enabled. |
The Broken Gates archaeological site can be discovered on any planet that's not a gas giant, asteroid or located in a black hole system.
Site | Chapter rewards |
---|---|
The Broken Gates![]() |
|
Chthonic Siren[edit | edit source]
![]() |
Available only with the Federations DLC enabled. |
If an empire is part of a Research Cooperative, then fully excavating any archaeology site has a 10% chance to start the event chain which reveals this site. Each member of the federation receives the site if a suitable system and planet exists within their borders, otherwise the member is given two special projects to support their federation allies with sites. Federation members can also opt not to participate.
Site | Chapter rewards with ![]() |
Chapter rewards without ![]() |
---|---|---|
Chthonic Siren![]() |
If all members who opted to participate complete their site or projects, the federation gains +40 cohesion and each member gains
6 minor artifacts and the Genius Caeli: A Time of Knowing empire modifier for 20 years. Otherwise, five years after any member fully excavates their site, if at least one other site is partially excavated or one special project set completed or similar total progress is made, the federation gains
+25 cohesion and each member gains
3 minor artifacts and the Genius Caeli: Balanced Prosperity empire modifier for 20 years. If no other site is excavated or special project set completed, the federation gains
−20 cohesion and each member gains
1 minor artifact.
Excavation events[edit | edit source]
At the end of an Excavation phase, if the result is not high enough to grant a Clue or finish the Chapter, then one of the following events may happen:
- Science Ship Scientist dies, −2 Clues
- Archaeology team members die, −1 Clues
- A dangerous situation is avoided, +3 Clues
- Choice to pay 100
Energy to get +3 Clues or do nothing and get −2 Clues
- Science Ship Scientist gains the
Maimed trait
References[edit | edit source]
- ↑ 1.0 1.1 If the technology has already been researched then Gain
96x research output (each potential yield gain of 2000 ~ 2000000) in the corresponding tech field
phy,
soc or
eng.
- ↑ Add this technology as research option with 30% progress.
- ↑ If this technology has already been researched then Gain
48x society output (potential yield gain of 1000 ~ 1000000) else gain this technology.
- ↑ Increased by having more than 500 monthly income of energy or minerals, more than 350 monthly income of unity, more than 200 monthly income of alloys, or more than 750 stored influence. Reduced by having less than 25 monthly income of energy or minerals, less than 20 monthly income of unity, less than 10 monthly income of alloys, or less than 100 stored influence. Each check is independent of the others.
- ↑ If this technology has already been researched then Gain
24x engineering output (potential yield gain of 500 ~ 1000000) else if this technology is a research option then gain 50% progress else add this technology as research option with 10% progress.
- ↑ If all colonization technologies have been researched then Gain
24x society output (potential yield gain of 500 ~ 1000000) else if this technology is a research option then gain 50% progress else add the next colonization technology as research option with 25% progress.
- ↑ 7.0 7.1 7.2 7.3 If this technology has already been researched then Gain
48x physics output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 50% progress else add this technology as research option with 10% progress.
- ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 If this technology has already been researched then Gain
48x society output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 50% progress else add this technology as research option with 10% progress.
- ↑ If this technology has already been researched then gain
100 volatile motes else if this technology is a research option then gain 50% progress else add this technology as research option with 10% progress.
- ↑ If this technology has already been researched then gain
2000 minerals else if this technology is a research option then 50% progress else add this technology as research option with 10% progress.
- ↑ 11.0 11.1 11.2 11.3 11.4 If this technology has already been researched then Gain
48x engineering output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 50% progress else add this technology as research option with 10% progress.
- ↑ If this technology has already been researched then Gain
96x society output (potential yield gain of 2000 ~ 2000000) else if this technology is a research option then 25% progress else add this technology as research option with 10% progress.
- ↑ If this technology has already been researched then Gain
96x engineering output (potential yield gain of 2000 ~ 2000000) else gain this technology.
- ↑ If this technology has already been researched then Gain
96x engineering output (potential yield gain of 2000 ~ 2000000) else if this technology is a research option then gain 50% progress else add this technology as research option with 10% progress.
- ↑ If this technology has already been researched then Gain
48x society output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then it gain 25% progress else add this technology as research option.
- ↑ If this technology has already been researched then gain
500 alloys else if this technology is a research option then gain 50% progress else add this technology as research option with 25% progress.
- ↑ If this technology has already been researched then Gain
48x society output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 50% progress else add this technology as research option.
- ↑ If this technology has already been researched then Gain
48x physics output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 50% progress Gain
24x physics output (potential yield gain of 500 ~ 1000000) else add this technology as research option and Gain
24x physics output (potential yield gain of 500 ~ 1000000).
- ↑ 19.0 19.1 If this technology has already been researched then Gain
48x society output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 25% progress else add this technology as research option with 10% progress.
- ↑ If this technology has already been researched then Gain
48x society output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 25% progress and Gain
24x society output (potential yield gain of 500 ~ 1000000) else add this technology as research option with 10% progress and Gain
24x society output (potential yield gain of 500 ~ 1000000).
- ↑ If this technology has already been researched then Gain
48x engineering output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 25% progress and Gain
24x engineering output (potential yield gain of 500 ~ 1000000) else add this technology as research option with 10% progress and Gain
24x engineering output (potential yield gain of 500 ~ 1000000).
- ↑ If this technology is a research option then gain 80% progress else add this technology as research option with 50% progress. No additional bonus for already possessing the tech.
- ↑ If this technology has already been researched then Gain
48x physics output (potential yield gain of 1000 ~ 1000000) else if this technology is a research option then gain 80% progress else add this technology as research option with 25% progress.
- ↑ Also adds a Special Project to repair the corvette damage.
- ↑ Not possible if scientist has
Maniacal or
Carefree .
Exploration | Exploration • FTL • Anomaly • Archaeological site • Relics • Pre-FTL species • Fallen empire • Events • Spaceborne aliens • Guardians • Marauders • Caravaneers |
Celestial bodies | Celestial body • Colonization • Terraforming • Planetary features • Planet modifiers |
Species | Species • Traits • Population • Pop modification • Species rights • Ethics |
Governance | Empire • Government • Civics • Policies • Edicts • Leader • Factions • Technology • Traditions • Situations |
Economy | Economy • Planetary management • Districts • Buildings • Holdings • Jobs • Designation • Trade • Megastructures |
Diplomacy | Diplomacy • Relations • Galactic community • Federations • Subject empires • Intelligence • AI personalities |
Warfare | Warfare • Space warfare • Land warfare • Starbase • Ship • Ship designer • Crisis |
Others | The Shroud • L-Cluster • Unique systems • Preset empires • AI players • Easter eggs |