History Main / TunnelNetwork

* In ''Discworld/{{Thud}}'', the dwarfs have created a tunnel network under Ankh-Morpork, partly so they can look for the McGuffin without anyone noticing, and partly because it wouldn't occur to them ''not'' to dig underground to where they want to go. By the end of the book, the network has been seized by the Patrician, who seems to have plans for it, possibly involving propelled carriages of some kind. (It's mentioned that the basic dwarfish mine sign, indicating a mine entrance, is [[TheTube a circle with a horizontal line through it]].)

* Dresden Files depicts a semi-fictional Chicago "Undertown".
* [[Creator/IsaacAsimov Isaac Asimov's]] ''Literature/TheCavesOfSteel'' features a very extensive road network underneath New York. It's restricted to police and emergency vehicles and is used by these to rapidly travel through the city. It's also considered fairly spooky even by the agoraphobic New Yorkers. Am in-universe ghost story has a criminal fleeing from the police into the labyrinthine tunnels to escape capture. He does... and then finds himself completely lost and unable to find somebody, anybody, to help him out. The story goes that his ghost haunts the tunnels still trying to find safety.

* [[Creator/IsaacAsimov Isaac Asimov's]] Literature/TheCavesOfSteel features a very extensive road network underneath New York. It's restricted to police and emergency vehicles and is used by these to rapidly travel through the city. It's also considered fairly spooky even by the agoraphobic New Yorkers.

[[folder:Tabletop RPGs]]

* ''TabletopGame/DungeonsAndDragons''. The Drow can move along underground passageways and emerge at various points on the surface.
* ''TabletopGame/CallOfCthulhu''. Several adventures with ghouls and chthonians give them underground tunnel networks. The ghouls' tunnels often connect to graveyards.
* The Skaven (rat-men) of ''TableTopGame/{{Warhammer}}'' have an extremely advanced network of tunnels often extending under cities and even under the ocean. Their main rivals are the dwarves, no slouches themselves when it comes to digging.
** In ''{{TabletopGame/Warhammer 40000}}'', [[RobotWar Necrons]] tomb-worlds have catacombs you could lose a cathedral in, housing thousands upon thousands of dormant Necron warriors. Regularly an Adeptus Mechanicus expedition drops in on one, {{squee}}s out at the [[AveMachina Machine God's]] gift, [[WhatAnIdiot and are promptly slaughtered when they start prodding around]]. The galaxy now has another Necron world to deal with.

* The Zerg in ''VideoGame/StarCraft'' have Nydus Canals.
* The GLA of ''VideoGame/CommandAndConquerGenerals'' have, well [[ExactlyWhatItSaysOnTheTin (hey, guess what?)]], [[http://cnc.wikia.com/wiki/Tunnel_Network Tunnel Networks]]. Each of their buildings also comes with a [[http://cnc.wikia.com/wiki/GLA_Hole underground bunker]]. If the building is destroyed but the bunker left alone a worker will emerge and rebuild the building.
* ''VideoGame/DawnOfWar'''s Imperial Guard buildings have this capacity, as well as certain catacombs in the Necron stronghold mission. While transport is instantaneous, there's a cooldown before a unit can be moved to another location regardless of the distance.
* Elaborate tunnel networks are typically created by many players of ''VideoGame/MineCraft''.
* In ''VideoGame/TheBattleForMiddleEarth 2'', both the Dwarven faction and the Goblin faction had resource-mining structures that doubled as entrances to their respective Tunnel Networks.
* Since fortresses in ''VideoGame/DwarfFortress'' tend to be mainly underground anyway, they usually incorporate some degree of this. Dwarven and goblin civilisations also create large tunnels linking settlements created during worldgen, and beneath those there are three levels of naturally-formed cavern system that blur the line somewhat between this trope and BeneathTheEarth.

* ''VideoGame/{{Fallout 3}}'' has a large number of Washington D.C's subway stations work as a limited Tunnel Network; given that much of the subway system and the buildings have collapsed, simply crossing the road is a complicated task..
** The Taft Tunnels appears to be purpose-built to be these, leading out from the Pentagon.
* ''VideoGame/DragonAgeOrigins'' has the Deep Roads, formerly a highway system for the dwarven kingdoms but now almost entirely held by the darkspawn.
* Tunnels under Rome serve as fast travel systems in ''Assassin's Creed: Brotherhood''.

* In ''VideoGame/{{Vietcong}}'', [[PlayerCharacter Hawkins]] infiltrates some of these.
* The [[AbsurdlySpaciousSewer Sewers]] in ''VideoGame/FalloutNewVegas''. [[AluminumChristmasTrees The real Las Vegas]] also has a drain tunnel labyrinth [[http://www.dailymail.co.uk/news/article-1326187/Las-Vegas-tunnel-people-How-1-000-people-live-shimmering-strip.html inhabited by 1,000 people]].
* The sewers of New York in ''VideoGame/FreedomFighters'' are utilized by the American Resistance to move about underneath the eyes of the occupying Soviets. In game, manhole covers mark points where you can quicksave and/or return to base if you find you don't have the right tools for the job at the moment. The subway tunnels are used similarly later on in the game.

For its high tech equivalent, see PortalNetwork. Occasionally related to AbsurdlySpaciousSewer. A SecretUndergroundPassage sometimes leads to this, but is technically a different trope. This refers specifically to a massive underground network of tunnels, not a single tunnel used for a singular purpose.

* The Geonosians in ''StarWars Clone Wars''.
* The Groundhog in ''CaddyShack'' has something like this.

* ''VideoGame/DawnOfWar'''s Imperial Guard buildings have this capacity, as well as certain catacombs in the Necron stronghold mission.

* The Zerg in ''StarCraft'' have Nydus Canals.

* ''AdvancedStrategicCommand'' allows to pool resources in buildings via either pipelines constructed by [[WorkerUnit bulldozers]] or inconvenient direct contact of buildings. Not only this saves bothering with transport, but producing some units require more materials than the factory or dock can hold. Buried pipelines are more expensive than open ones, but preferrable: they doesn't hinder unit movement and to break one the enemy must bring a [[WorkerUnit construction unit]] to it instead of simply bombing. Construction ships can build underwater pipelines to connect islands.

* The TV ''Series/BeautyAndTheBeast'' had an extensive underground network in association with the NY subway system, with a whole Secret Society down there.

* ''{{Boneshaker}}''. Seattle has a network of sealed tunnels because above-ground is infested by zombies and the DeadlyGas that creates them.

* ''{{Traveller}}'' Classic Double Adventure ''Death Station''. The drugged humans on a space station have cut through the deck and cut holes in the fuel tanks to create underdeck passages throughout the ship.

* The GLA of ''VideoGame/CommandAndConquer: [[CommandAndConquerGenerals Generals]]'' have, well [[ExactlyWhatItSaysOnTheTin (hey, guess what?)]], [[http://cnc.wikia.com/wiki/Tunnel_Network Tunnel Networks]]. Each of their buildings also comes with a [[http://cnc.wikia.com/wiki/GLA_Hole underground bunker]]. If the building is destroyed but the bunker left alone a worker will emerge and rebuild the building.

* Elaborate tunnel networks are typically created by many players of ''MineCraft''.
* In the ''The Lord of the Rings: The Battle For Middle-Earth 2'' game, both the Dwarven faction and the Goblin faction had resource-mining structures that doubled as entrances to their respective Tunnel Networks.

* The eponymous institution in TalesOfGnosisCollege has an extensive network of steam tunnels running underneath its campus, which it happens to share with an adjacent Catholic women's college. Eventually some enterprising students put them to the obvious use.

* The Skaven (rat-men) of {{Warhammer}} have an extremely advanced network of tunnels often extending under cities and even under the ocean. Their main rivals are the dwarves, no slouches themselves when it comes to digging.
** In Warhammer40K, [[RobotWar Necrons]] tomb-worlds have catacombs you could lose a cathedral in, housing thousands upon thousands of dormant Necron warriors. Regularly an Adeptus Mechanicus expedition drops in on one, {{squee}}s out at the [[AveMachina Machine God's]] gift, [[WhatAnIdiot and are promptly slaughtered when they start prodding around]]. The galaxy now has another Necron world to deal with.

* On ''HogansHeroes'' they had a network of tunnels under the camp, and leading out of camp.

* In ''{{Pyrates}}'', there's a large network of tunnels and caves underneath New York City, used both by homeless people simply to survive, and by smugglers and thieves.

* ''DawnOfWar's'' Imperial Guard buildings have this capacity, as well as certain catacombs in the Necron stronghold mission.

* [[DisneyThemeParks Walt Disney World]] has such a network to hide certain aspects of park operations from the customers (trash collection being primary).

* Laval University in Quebec has all of its buildings linked by tunnels, so people can avoid being outdoors during the winter. Wright State University in Ohio has a similar system, with only two or three buildings left out of the loop.

* In ''Literature/GoodOmens'', there's a sequence where various New Age beliefs start coming true, of which one is the conspiracy theory that the Secret Masters of the World live in a cave beneath Tibet and travel around through an extensive tunnel system. This results in things like gardening programs offering tips on what to do if a nosy Tibetan monk pops up in the middle of your flower bed.

* WaltDisneyWorld has such a network to hide certain aspects of park operations from the customers (trash collection being primary).

* The Silence have a whole network spanning the entire surface of the Earth in {{Doctor Who}}, allowing them to control the human race without them knowing.
* The {{Torchwood}} 3 team were based in one that included a disused secret underground railway connecting them (Cardiff) to London and Scotland.