Main Article Theories about
Subterranean conduit
Main Discussion
 Theories may be removed if ... 
  1. Stated as questions or possibilities (avoid question marks, "Maybe", "I think", etc).
  2. More appropriate for another article.
  3. Illogical or previously disproven.
  4. Proven by canon source, and moved to main article.
  5. Speculative and lacking any evidence to support arguments.
  6. Responding to another theory (use discussion page instead).
  • This does not include responses that can stand alone as its own theory.
  • Usage of an indented bullet does not imply the statement is a response.

See the Lostpedia theory policy for more details.

There are various pieces of evidence suggesting the location of interconnecting tunnels between specific points on the island, most likely accessible from places close to the stations.

  • It was the name of the intranet mentioned on the map
  • The catastrophic incident deemed travel unsafe so the The Swan's Conduit port was filled in with cement to block it off
  • Could be a lava tube system, which is common on volcanic islands.
    • This could be how the Others travel so quickly and quietly around the island.
  • The conduits are how the Others get in and out of the barracks past the sonic barrier


  • Could be shown on the blast door map
    • It has interconnecting lines between the stations, which could represent the tunnels.
    • Could be represented on the map by the blue windy channel that meanders around the The Swan, The Flame, and the ? (The Pearl). These three were the only stations accessible by the Conduit.
  • In "Exodus" the monster tries to drag Locke into a hole in the ground, quite possibly part of a tunnel system.
  • In the episode "A Tale of Two Cities," Ben is seen ordering Goodwin and Ethan to infiltrate the Tailies and the Middle-Section Survivors' camp respectively. Although he does suggest they run, the speed at which they arrive suggests a possible Underground Metro System, or tunnels that they can at least run down, as this would undoubtedly save time, especially when considering the dense forest they would be forced to sprint through.
  • We learn in "A Tale of Two Cities" that The Hydra is underwater, meaning it is in fact possible to build underground on the island. Also, it is likely that The Others use some form of tunnel to exit the underwater facility.
  • The other Stations on the island, such as The Swan also show underground facilities exist. The fact that the doors are marked 'Quarantine' also insinuates that there must be a 'safer' way to travel between stations than by going outside.
  • Rose claims that the noise the Monster makes is familiar. She is known to come from the Bronx, in New York city, which has an underground metro which makes a noise similar to that of the Monster when a train is passing. This could mean the noise was not actually coming from the Monster, but from below the ground. It could also mean that the Monster is in fact caused by a passing underground car or train, perhaps something to do with the magnetism of the island.
  • The Capsule Dump shows evidence of an underground pipe system, albeit on a much smaller scale. Again, this proves the ground is adequate for building tunnels, and indicates that The Others preferred a tunnel system as a means of transportation.
  • When Ben escapes from The Swan, he leaves no visible trace, a common trait of their movement. Of course, this may be simply because they know the island well, though this is made questionable in several instances, such as when Goodwin is alarmed to see a radio in The Arrow when he enters with the Tailies, as though he did not know it (or even the station itself) was there. Therefore, their method of travelling around the island so evasively may be down to underground tunnels.
    • It is worth bearing in mind, however, that Goodwin's apparent surprise at discovering the station may simply have been an act; he was pretending to be a survivor, after all.
  • The producers stated that the glyphs are symbols of the "underworld". They may actually be referring to the underground conduits mentioned on the BLD and seen when Locke is nearly sucked into the hole by the smoke monster. The underworld could be the Monster's means of transportation, or perhaps an underground travel method for the DHARMA people. The glyphs may represent the magnetic build-up or the-like in this underworld. The existence of this underworld is substantiated by the fact that all the hatches have power which likely comes from a central point, perhaps the Swan. As well, the Staff has an escape hatch and the Swan did before the incident, which may lead into these conduits.
  • The Barracks is quite a modernised place, implying that The Others are not particularly 'at one with nature,' thus meaning that they would not be quite so apt at travelling around so secretly, again pointing to the tunnel theory as a means of travel.
  • As the island appears to run on geothermal power (which would be concentrated in certain spots,) electric cables would be needed to run to different stations, and a tunnel would be a perfect location for such a thing.
  • In 'Every Man For Himself' we learn there are in fact two islands, the Hydra Island and the Main Island, and a tunnel is a possible means of transportation between the two. There is also reference to a 'Submarine,' which may in fact refer to an underwater tunnel, as submarine does not refer strictly to the vehicle of this name.
  • Tunnels are shown going in and out of the barracks on the DHARMA Cabling Map

Flaws In The Tunnel Theory

  • Even though the others move without leaving tracks, then why when Tom and another other were transporting Colleen from the sailboat to the Hydra, were they trekking through the jungle? Using a tunnel system would prove much faster.
    • This could be because there are no tunnels at this location, or it may have been quicker to simply walk instead of diverting to the tunnel entrance.
Community content is available under CC BY-NC-ND unless otherwise noted.