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This article is about the Aperture Science ship. For the location cut from Half-Life 2, see Borealis (cut location).
"Our peers at Aperture Science were at work on a project of some promise, but in their rush to beat Black Mesa for funding, they must have compromised ordinary standards of risk. We heard their research vessel had simply disappeared. Vanished with all hands... even part of the dry dock!"
Isaac Kleiner[src]

The Borealis is an Aperture Science research vessel introduced in Half-Life 2: Episode Two. According to Isaac Kleiner, Aperture was working on a promising project, but in their rush to beat Black Mesa for funding, they neglected ordinary safety rules and the ship simply disappeared with parts of its drydock, which earned it a legendary stature.

It is assumed that the Borealis contained an immensely powerful and dangerous secret, most likely involving portals and teleportation on a larger scale than that of a handheld portal device, which is likely the reason the Combine are searching for it as they could possibly connect back to Combine Overworld and flood the planet with their large and powerful armies. The Combine also have yet to perfect localized teleportation, as the Black Mesa scientists and Aperture Science have, giving them ample reason to investigate the ship.


Mossman vid base

Mossman sharing her discovery with the Resistance.

Half-Life 2: Episode One

Many years after the Combine invasion of Earth, Judith Mossman, Resistance operative, finds the Borealis in an Arctic location. She is attacked by Combine forces soon after, and is only able to send an incomplete transmission of her discovery to White Forest. This is intercepted by the Combine, and in turn stolen back by Gordon Freeman and Alyx Vance from the Citadel Core during their flight from City 17.

Half-Life 2: Episode Two

After safely reaching White Forest, Alyx and Gordon deliver the data to the Resistance, which reveals that Mossman was cunning enough to encrypt Borealis photographs, coordinates, blueprints and hailing frequencies within her message. Once Eli Vance and Isaac Kleiner have decoded these and realize the full significance of the transmission, a rift opens between the two Resistance leaders. Kleiner believes the technology the Borealis contains could be used by the Resistance against the Combine to aid them in The Uprising; Eli, haunted by memories of the Black Mesa Incident and not wanting a second Seven Hour War, believes that the Borealis has to be destroyed at all costs.

It is not clear whether the Combine know of the Borealis, and consequently if they themselves have some interest in the ship's contents. Given the attack upon Mossman's forces, the interception of her message and the death of Eli Vance, it seems very likely.

While the nature of the secret hidden within the Borealis is unknown, one of the blueprints indicates the presence of at least a Material Emancipation Grill and an Unstationary Scaffold within the ship.

Mossman's message goes as follows:

I'm fairly sure I've pinned down the location of the Project. It's hard to say how much of it might have survived intact, or whether there's anything remaining that could compromise our work... if it were discovered by the Combine. We'll need to take a close look at it, of course, but I should be able to give a better opinion within a few hours. If the site is where we think it is, then it should be no more than... I'm going to cut this short. We may have been spotted.

Portal 2

Borealis drydock

The Borealis' empty dry dock.

In Portal 2, the Borealis' dry dock can be found in the 1970's section of Test Shaft 09, near the offices where Chell finds GLaDOS in the bird's nest. The dry dock is obviously empty, save for several life preservers bearing the ship's name scattered on the floor.
Portal 2 Borealis Lifering

Borealis life Preserver

This is an uncommon location in which to place a large ship; the elevation of the dry dock is approximately 3975 meters below the surface, as noted on the wall in the nearby inaccessible lobby of the main shaft elevator on this level. There is no other mention of the ship's presence in, or disappearance from this area, though it may have simply teleported out.

Next to the entrance of the dry dock there is an intercom where Cave Johnson mentions that they are working on a teleportation experiment, leading the player to believe that the ship was teleported. This appears to agree with the fact that perfecting localized teleportation was something the Combine and the Resistance were working on in Half-Life 2 and its episodes.

Half-Life 2: Episode 3 / Half-Life 3

Borealis Advisors

Concept art for Episode Three

The Borealis is expected to appear in Episode Three. The first revealed concept art features a ship, with the word "B--EALIS" on it, the O and R being covered by Combine technology. It is stuck in ice, and Advisors float through the canyon, suggesting that the Combine will have already discovered the ship when and if Gordon reaches it.

Behind the scenes

Borealis E3 screen

The Borealis as it was first shown to the public.

  • The icebreaker Borealis was originally to appear in Half-Life 2, as the Hyperborea, then the Borealis. In Marc Laidlaw's first pass at the game's script, Freeman was to start the game by boarding the ship, bound for City 17.[2] Later in the game's development, it was to appear between two other cut chapters, the Air Exchange and Kraken Base,[3][4] before being eventually cut with the whole part set between the Depot and the City 17 street battles.
  • The name "Borealis" is likely associated with the term "aurora borealis", the northern polar lights only visible in the Northern Hemisphere. "Borealis" comes from "Boreas", a wind god in the Greek mythology. "Hyperborea", the early name for the ship, was the name of the land of the Hyperboreans, a mythical people who lived far to the north of Thrace. "Hyperborea" means "beyond the Boreas," thus beyond the land of the wind god Boreas. "Aurora Borealis" is also the name of a European research icebreaker being constructed.[5]
  • The images hidden in Mossman's message are located in the Episode Two texture files, in the folders "effects" and "Props".
    • Other images include three blueprints of the Borealis. The original images are not blueprints for any of the United States Coast Guard research icebreakers mentioned above but those of a naval warship, the USS Newport News, a United States Navy heavy cruiser launched after World War II. They also feature tables, taken from other blueprints. The images also feature a QSL card, originally for the USCGC Polar Star.
  • The Borealis seen on the screen at White Forest can be found within the map "ep2_outland_11b" and accessed with the "noclip" console code.

"Ship Overboard" Achievement icon.

  • One Portal 2 Achievement named "Ship Overboard", with the description "Discover the missing experiment", requires Chell to find the Borealis' dry dock.


  • The Borealis' teleportation mishap shares many similarities to the urban legend of the Philadelphia Experiment in which the warship USS Eldridge was rumored to have been rendered invisible by experimental technology. In some versions of the story, the ship had accidentally teleported from its dry dock to a U.S. naval base over 200 miles away. In the most radical versions of the story, the ship achieved accidental time travel.
  • While the Borealis was apparently located in an area of the Enrichment Center built in the 1970s, the ship's blueprints feature GLaDOS' name where the corporation's owner would sign, as well as the modern Aperture Laboratories logo. This issue has yet to be addressed or retconned.
  • As stated in an email from GLaDOS to GLaDOS, the Borealis was designed to be very durable, while everyone thought that it was a simple icebreaker ship. It also had very little in the way of supplies for a crew, and was stripped of anything not necessary for so that there was a lot of space for it.[6]
  • The mappack for Portal: The Flash Version, made before Portal 2's retcon, features a cameo appearance of the Borealis in the modern Aperture facility. In an office is a panel that shows the blueprints seen in Episode Two, and a red button which activates a crane that delivers a group of Personality Constructs to a crate on the ship (It's mandatory to push this button, as it also unlocks a door nearby).
  • Valve made a shirt available on their website which depicted the Borealis' life preserver with the words "Never Forget" written on it.[7]


Game files




List of appearances