''Railsea'' is a novel by ChinaMieville, officially YoungAdult. However, the "young adult" part mainly means a lack of swearing, sex or graphic violence, rather than any lack of mindbendingness.

Sham ap Soorap is an unhappy surgeon's mate on the ''Medes'', a moling train than plies the lethal ground of the railsea & hunts the giant moldywarpes that live at the top of its food chain. Especially Mocker-Jack, the huge blond moldywarpe that took Captain Naphi's arm. But when Sham is picked to search a wrecked train, he finds himself in possession of a {{MacGuffin}} that various nasty people are looking for.

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!!Tropes:
* ActionGirl: Several, especially Caldera, Naphi & Sirocco.
* AdventurerArchaeologist
* AfterTheEnd: Although some time after, & nobody really remembers the details.
* AlienSky: The sky over the railsea, where [[{{Kaiju}} massive atmospheric beasts]] watch for prey from among the toxic clouds.
* AmbiguousGender: Dr. Fremlo.
--> "So you going to be a moler's doctor, Sham?" Timon said. Sham shrugged. "Going to turn out like your boss? No one knowing if you're a man or a woman?"
--> "Shut up," Sham said uncomfortably. "Fremlo's Fremlo."
* AndTheAdventureContinues: [[spoiler:The ending has the main characters going off to seek adventure on an even bigger scale.]]
* AnimalNemesis: Parodied. The town that Sham comes from expects every '''real''' hunter to have one. It is referred to as 'having a philosophy.'
* AttackOfThe50FootWhatever: The railsea is filled to the platforms with various oversized, predatory critters, from man-sized leaping deathworms to burrowing owls big enough to wrestle trains off their tracks. Mocker-Jack, the giant mole that Naphi spends the book tracking down, goes straight into {{Kaiju}} territory.
* BlueAndOrangeMorality: The angels are described as such. The railgoing ones are dedicated to keeping the tracks clean above all else. "All else" including whether or not there's still a train on the tracks they're about to roll through.
* BrotherSisterTeam: Caldera & Dero Shroake.
* CallARabbitASmeerp: Most of the weirder creatures that seem mundane have weird names like the giant moles, birds, & some insects.
* CavalryBetrayal: The Manihiki army
* CoolBigSis: Sirocco, the friendly salvager who frequently stops by to lend our heroes a hand.
* CoolTrain: Many, especially the ''Medes'' & the Shroakes' exploration train.
** The Angels (at least, the ones that travel on tracks).
* DerelictGraveyard
* DesertPunk: Takes place on an "ocean" that's a monster infested wasteland dotted with raised "islands" & crisscrossed with railways whose trains are treated much like ships so in a weird way it manages to combine both this ''&'' OceanPunk. [[spoiler:The ending implies that the crew of the ''Medes'' are leaping headfirst into the latter genre.]]
* DieselPunk: Since it seems most technologies of the current era run off fossil fuels & everything has a mixed air of the idealized 1930's and 1940's both good & bad, this certainly fits.
* DrillTank: Sirocco's vehicle
* GiantFlyer: The denizens of the upsky, which also cross over into StarfishAlien territory. They're explicitly described as alien, too.
* TheEmpire: Manihiki is somewhere between this & an unsympathetically-portrayed EagleLand version of TheFederation, a supposed democracy with a major gap between rich & poor & a nasty imperialist streak.
* EverythingTryingToKillYou: The ground outside the rock "islands", the "up-sky", oh & the lack of cover anywhere from the things below.
* GhostShip At least a few of these, especially the wrecked ones.
* GhostTown: Plenty of them in the background. [[spoiler:Heaven]] is the most significant on-screen example.
* [[HasTwoMommies Has Two Daddies]]: Caldera & Dero. & a mummy as well.
* HistoricalInJoke: One of the gods is "Railhater Beeching." He's named after Dr Richard Beeching, notorious in Britain (perhaps unfairly so) for closing vast numbers of railway lines.
* TheHunterBecomesTheHunted: Early on, Sham finds a salvaged tracker that he presents to Naphi, who later on uses it to tag Mocker-Jack. [[spoiler:It turns out that the device works both ways, & a very annoyed Mocker-Jack is now homing into the ''Medes'' with the purpose of wrecking it once and for all. [[EgomaniacHunter All according to plan for Naphi]].]]
* InsistentTerminology: Mocker-Jack, Captain Naphi's AnimalNemesis, is not yellow. He's ''ivory''. Also, the consistent use of '&' in place of 'and', which actually gets discussed in one chapter.
* LastBastion / LostWorld: [[spoiler:Subverted - the controller & 'Heaven's Citizens' have turned into degenerate primitives & the Railsea dwellers are doing much better than they are.]]
* LayeredWorld: Not literally. But it's common knowledge that the sky has two layers & the world has four.
** The sky is divided into the "downsky", which is basically normal. Then, two or three miles up, the downsky is suddenly replaced by the lethally poisonous "upsky", home to various unpleasant & gigantic alien flyers.
** The first layer of the ground is the underground "subterrestrial", home to all the tunneling monsters that inhabit the railsea. Above it is the second layer, the railsea itself. Above the railsea is the third layer, consisting of all the habitable islands & continents, & above those are the fourth layer: the highlands, high enough to jut into the upsky itself.
* LemonyNarrator
* LowCultureHighTech: Played with. Though the dwellers of the railsea seem to be doing fine with their [[CoolTrain trains]], primitive biplanes & advanced digital recorders/trackers, their lack of understanding of the world's nature, along with the generally strung-out cultures of the various rock-island civilisations & weird linguistics, gives off a general impression more reminiscent of, say, the Golden Age of Piracy than anything else.
* MegaCorp: [[spoiler:The world became the way it is now due to an apocalyptic trade-war between several of these.]]
* MobySchtick: The plot involving Naphi & Mocker-Jack.
* MorePredatorsThanPrey: Lampshaded in the narration.
* NotSoSafeHarbour: Bollons
* ObfuscatingDisability: [[spoiler:Naphi.]]
* SandWorm: A whole ecosystem of them, of invertebrate, mammalian & even avian varieties.
* ScavengedPunk
* ScavengerWorld
* SchizoTech: The "modern" trains run off diesel, but they share the tracks with various analogues powered by {{steam|Punk}}, {{clock|Punk}}work, "[[AppliedPhlebotinum hermetic engines]]", [[RuleOfCool sails]] & ''rhinos''.
* ShoutOut: To RoadsidePicnic (with the incidental mention of the name Strugatsky) & ThomasTheTankEngine (with the top-hatted god named That Apt Ohm - a SignificantAnagram)
** There is also a ShoutOut to the 1969 film 'The Bed-Sitting Room', in which Mrs Ethel Shroake (of 393A, High Street, Leytonstone) is the closest surviving successor to the throne of Great Britain.
* SummonBiggerFish: Multiple examples. The first one is when [[spoiler:Sham escapes from the pirate train ''Tarralesh'' when it gets shot to bits by a Manihiki wartrain]]. Said assailant reappears to chase down the ''Medes'' at the climax, only to be [[spoiler:vaporised by a rail angel. With the angel now hot on their tracks, Sham & Sirocco decide to [[CrazyEnoughToWork lure in Mocker-Jack with a two-way tracker]], which eventually culminates in the philosophy & the angel fighting & plummeting down [[BottomlessPits a chasm]]]].
* {{Terraforming}}: [[spoiler:The railsea used to be an actual sea, before a great company war in aeons past drained it up to lay tracks over.]]
* TransplantedHumans: It is mentioned at least twice that the humans of this world come from another & at one time had space travel.
* TreasureMap
* UnnecessarilyCreepyRobot: The "Angels" both flying & on rail; they are portrayed in an almost 'demonic' fashion & feel very creepy in both description & the Railsea dweller's fears.
* UnroboticReveal: [[spoiler:Naphi, when her "prosthetic" arm gets damaged & starts bleeding, revealing that she was ObfuscatingDisability all the time.]]
* WholePlotReference: As previously mentioned, it's a ''really weird'' version of Literature/MobyDick.
* WordSaladPhilosophy: Captain Nathi spouts one of these when it's revealed that [[spoiler: she still has both arms.]] Vurinam notices.
-->''"That don't even bloody ''mean'' anything!" he despaired. "It's complete bloody gibberish!"''
* YouHaveOutlivedYourUsefulness: [[spoiler:The crew of ''Tarralesh are [[{{Privateer}} government-sanctioned privateers]], not pirates. This stops mattering when they refuse to hand over Sham to [[CurbStompBattle the Manihiki ferronavy]].]]
* ZillionDollarBill: [[spoiler:It turns out that the nameless MegaCorp that built Heaven (along with all of the railsea) were charging the trainsfolk with usage fee, & their feral descendants are living with the prophecy that the users will one day return to pay the accumulated debt of many, many lifetimes (with interest).]]
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