[[quoteright:329:[[ComicBook/DisneyDucksComicUniverse https://static.tvtropes.org/pmwiki/pub/images/DonaldMine.jpg]]]]
[[caption-width-right:329:Much more impressive than [[FishingForSole a boot.]]]]

->''Any ship can be a minesweeper. Once.''

Ah, naval mines. Just the thing to catch [[UsefulNotes/TypesOfNavalShips unwary vessels.]]

The use of these UsefulNotes/NavalWeapons is still legal [[LandMineGoesClick unlike the anti-personnel land-based version]], but you are required to notify people of their use and the rough location of them, so civilian shipping can stay out of the way.

Naval mines in fiction are always portrayed as large metal spheres covered with small spike-like detonators which cause the mine to explode on contact with a ship (or any unfortunate individual). This is based on the appearance of early naval mines. Most modern ones look rather different. Some are self-contained launch tubes for a [[http://en.wikipedia.org/wiki/CAPTOR_mine homing torpedo]] that launches when it detects the sound of a ship or submarine's propellers (and is smart enough to distinguish between the two, or even different classes and sizes of ship, and may be set to attack either or both). Others are [[UsefulNotes/AirLaunchedWeapons modified aircraft bombs]] dropped in shallow waters to lie on the sea bed, with sensor circuitry that detonates when they detect the change in magnetic fields created by the ship's metal hull. The horned type, however, remains a favored weapon for shallow waters and low budgets, and like the CartoonBomb is easily recognized by the viewing public.

That page picture has a grain of TruthInTelevision to it, by the way; Just as unexploded ordnance is regularly found on land around the United Kingdom and Continental Europe, fishing trawlers working in the English Channel or the North Sea really do pull live mines, torpedoes and other Second World War-era munitions out of the depths [[OhCrap every so often]].
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!!Examples:

[[foldercontrol]]

[[folder:Anime and Manga]]
* The [[Anime/DigimonFusion Digimon]] Chikurimon is one.
* ''Anime/MazingerZ'': In episode 22, [[TheDragon Baron Ashura]] used electric sea mines -called Balanger M1-. They were light blue with dark blue spikes that covered its bodies, and they were able to move through water and home in on an opponent. Once they came into contact, they released electric charges to hurt their target. [[MonsterOfTheWeek That episode also featured]] [[{{Robeast}} Mechanical Beast]] Balanger M2, a [[TransformingMecha giant robot capable to transform]] into a red, spiky, electric sea mine.
* ''Anime/RurouniKenshin'': In the last manga arc, [[SmugSnake Heishin]] used sea mines to protect his organization's [[IslandBase base]]. They looked like the classic type and they were stored inside wooden cages.
* ''Manga/ArpeggioOfBlueSteel'', set in a navy-based future, doesn't use the round ones, instead opting for modern sea mines like hidden torpedo launchers. The comparison is still made though.
[[/folder]]

[[folder:Comic Books]]
* During the ''ComicBook/BatmanNoMansLand'' BatFamilyCrossover that ran through ''ComicBook/{{Azrael}}'', ''ComicBook/{{Batman}}'', ''ComicBook/{{Catwoman}}'', ''ComicBook/DetectiveComics'', ''ComicBook/{{Nightwing}}'', ''ComicBook/Robin1993'', and ''ComicBook/YoungJustice'' there were mines placed in the ocean and rivers surrounding Gotham City to prevent those trapped there from escaping.
[[/folder]]

[[folder:Film - Animation]]
* ''WesternAnimation/FindingNemo'': The sharks live in a sunken warship surrounded by "balloons". They become a ChekhovsGun [[spoiler:when a berserk Bruce accidentally sets one off with a torpedo while trying to kill Marlin and Dory, which sets off a chain reaction with the other mines, causing the sharks to flee.]]
* ''WesternAnimation/GuillermoDelTorosPinocchio'': Taking place in war-torn UsefulNotes/FascistItaly, the ocean is full of sea mines, first introduced by a seagull accidentally setting one off by sitting on the trigger. Pinocchio later [[spoiler:uses a sea mine to blow up the inside of the Dogfish, freeing him and killing the beast, but blowing his father and friends in the process]].
[[/folder]]

[[folder:Film - Live-Action]]
* ''Film/JamesBond''
** In ''Film/{{Moonraker}},'' Bond's [[CoolBoat Amazon boat]] has a number of these in its arsenal, which Bond releases to blow up a pursuing boat.
** At the beginning of ''Film/ForYourEyesOnly'', a British spy trawler is sunk after a sea mine was pulled up in its nets. It seems like a freak accident, but a scene of similar mines stored in a warehouse owned by the BigBad suggests otherwise. TheDragon blows one of them up to effect his escape from 007.
* ''Film/GodzillaMinusOne''. Shikishima takes on the well-paid but dangerous work of clearing the thousands of sea mines laid in Japanese waters during the war. Clearing involves two small boats made of wood (to avoid setting off magnetic mines) towing a cable between them to cut the mine's tether so it will float to the surface and be detonated with gunfire. When Godzilla makes an appearance, they are ordered to use some of these cleared mines to try and stop it. Naturally the crew think this is even more suicidal than their usual job.
* ''Film/HotFuzz'', except it's not underwater when we see it, it's ''lying around in some dude's garage''. Though initially appearing to be a dud, it quickly starts ticking once Angel and Danny find it. [[spoiler:DoubleSubversion; it doesn't go off, and it ends up stored in the evidence locker with Angel believing it's deactivated. It winds up [[ChekhovsGun going off]] during the PostClimaxConfrontation with Tom Weaver]].
* ''Film/TheHeroesOfTelemark'' have to fend off a mine with a big pole while escaping from Norway.
* The protagonists of ''Film/TheCityOfLostChildren'' have to navigate through a bunch of these to get to the lair of the resident MadScientist.
* An unrecovered sea mine from WWII is what sinks ''HMS Trojan'' in ''Film/MorningDeparture''.
* ''Film/VoyageToTheBottomOfTheSea''. After the sonar is sabotaged, the submarine almost plows headfirst into a field of underwater mines, and a tense sequence starts when they have to send in a minisub to cut a mine cable they've gotten entangled with. When the cable is cut, the mine drifts up and sets off another mine, and the underwater blast sends the minisub into a third mine which destroys it. It's not clear what the minefield is doing there given that there isn't a war on; either it was planted recently to stop the ''Seaview'' or it's an uncleared minefield from a previous war.
[[/folder]]

[[folder:Literature]]
* A supertanker in the first chapter of ''Literature/WinLoseOrDie'' has to tread the waters of [[ChokepointGeography Straits of Hormuz]] carefully, as the previous eight years of UsefulNotes/IranIraqWar has left it filled with mines, and they have no assistance of clearing them from British and US navies. Little do they know that the real danger comes from above, not below.
* In ''[[Literature/SixteenThirtyTwo 1634: The Baltic War]]'', using an uptime encyclopedia the Danish develop mines to help defend against the USE Navy. However, given King Christian is more enamored of AwesomeButImpractical weapons, it's only done as a side project, not producing enough devices (which resemble the stereotypical spiked sphere) to have much of an effect, though they do manage to utterly destroy one of Admiral Simpson's ironclads in their one deployment before the conflict against Denmark is concluded.
* A [[UsefulNotes/BritsWithBattleships Royal Navy]] submarine's loss in ''Literature/RedStormRising'' is hypothesized to be due to a decoy for a [[UsefulNotes/RedsWithRockets Soviet]] submarine being planted in the middle of a minefield.
* In ''The Mandarin Cypher'', British spy Literature/{{Quiller}} is doing a scuba infiltration of a Chinese oil platform that turns out to be protected by sea mines, a fact that he doesn't realise in the dark [[OhCrap until the detonation horns have bumped against him]], fortunately not hard enough to detonate it. He detaches the mine from its cable and [[ChekhovsGun stashes it for later use.]]
* An aerial version occurs in ''Literature/TalesOfTheKettyJay''. In order to reach the secret SkyPirate hideout of [[NotSoSafeHarbor Retribution Falls]], the crew of the Ketty Jay have to [[BlindDriving blind-fly]] their CoolAirship through mist-shrouded ravines using a map and a MagicCompass--and they have no idea what the latter does. Turns out the compass reveals the location of the aerial magnetic mines that protect Retribution Falls.
[[/folder]]

[[folder:Live Action TV]]
* The 1970's Australian series ''[[https://en.wikipedia.org/wiki/Patrol_Boat_(TV_series) Patrol Boat]]'' had an episode where a Japanese [=WW2=] sea mine had drifted inshore, but blowing it up would mean destroying some historical Aborginal cave paintings.
* Done in the first series of ''Series/SeaPatrol'' (also an [[RecycledPremise Australian series about a patrol boat]]), when a mine washes up on a beach after a cyclone. While it is unstable, the only real danger comes from a pair of TooDumbToLive preteen boys who find the mine and don't report it straightaway. One even runs towards it to save a tortoise when the {{bomb disposal}} unit are about to destroy it.
* One of these washed up in the lagoon in an episode of ''Series/GilligansIsland''.
* ''Series/DadsArmy'': In "Menace from the Deep" the Walmington-on-Sea platoon is stranded on the Walmington-on-Sea Pier. The situation becomes worse when a sea mine drifts underneath the pier. When Hodges falls off the pier, the magnetic mine is attracted to his steel helmet.
* In the 1977 BBC series ''The Secret War'', the episode "The Deadly Waves" examines the LensmanArmsRace between the Allies and Nazis over the magnetic sea mine.
[[/folder]]

[[folder:Manhua]]
* Spoofed in one ''Manhua/OldMasterQ'' strip. The titular character is chilling out in the waters of a beach when his rival, Chiu, pulls the [[SharkFinOfDoom rubber-sharkfin-on-head]] gag causing Master Q to flee in panic. When Master Q finds out, he retaliates by pretending to be a naval mine while Chiu is fishing on a boat, causing Chiu to zoom away like crazy.
[[/folder]]

[[folder:Other]]
* Naval mines were used in the 1998 MBX ''The Battle of Brunei''. The Malaysian naval commander gave the RefugeInAudacity order that the minefields be regularly [[http://en.wikipedia.org/wiki/Chumming chummed]].
* Dutch comedy Audio series Ome Henk has the titular Uncle Henk berate his Director for misinforming his nephew Jantje for calling a Seamine a Buoy. His nephew responds by [[StuffBlowingUp throwing it away, causing a GINOOOOOOOORMOUS explosion]]. [[RunningGag As per usual.]]
* It's widely accepted that a Navy Mine sunk the Hospital Ship The ''HMHS Britannic''(sister ship of the ''Titanic'') The 2000 Made for TV Movie however played with the alternate theory of a submarine torpedo but in the end it was the work of a [[VehicularSabotage saboteur]].
* Common in the old ''Magazine/{{MAD}}'' magazine standby, ''ComicStrip/SpyVsSpy''. Sometimes they were hidden in innocent-looking items as a trap, other times they were [[HoistByHisOwnPetard turned on their owners]], but it was as good as guaranteed that seeing one in the setup would result in an explosion by strip's end.
[[/folder]]

[[folder:Radio]]
* ''Radio/TheGoonShow'': "The Dreaded Batter Pudding Hurler".
-->'''Eccles:''' MINE AHEAD! Dirty big mine ahead!
-->'''[[DirtyCoward Bloodnok]]:''' Mi—? ''(footsteps running into the distance, splash)''
-->'''Neddie Seagoon:''' Funny, he wasn't dressed for swimming.
-->'''[[TooDumbToLive Eccles]]:''' Wait, fellas, there's no need to worry about the mine — it's one of ours!
-->''(KABOOM)''
* ''Radio/TheNavyLark'': ''HMS Troutbridge'' once thought they had salvaged a missing American satellite. What they had actually found was a World War II era sea mine. HilarityEnsues.
* ''Radio/TheMenFromTheMinistry'' episode "The Thing on the Beach" revolves around a sea mine on an English beach-resort that Mr. Lamb is forced to defuse. [[spoiler:At the end of the episode it turns out to be a mine-shaped collecting box.]]
[[/folder]]

[[folder:Tabletop Games]]
* ''TabletopGame/BattleTech'' allows for the deployment and use of minefields as part of its advanced (i.e., not strictly tournament-standard) rules. This includes explicitly sea-based conventional, inferno, or command-detonated minefields; inferno mines only work on the surface, the other two can be placed at any given depth.
* Widely used in ''TabletopGame/{{Harpoon}}''.
* ''TabletopGame/{{Space 1889}}'' the adventure Canal Priests of Mars have an aerial version.
* In ''TabletopGame/SalvageHiddenTreasures'', these can be encountered as events, and it costs the player half the money they have to repair their ships.
[[/folder]]

[[folder:Video Games]]
* ''VideoGame/AquaJack'' have floating mines everywhere, since the game have you piloting a speedboat kicking ass while traveling along rivers and streams. They need to be shot at or jumped over to avoid taking damage, and there's even a hovercraft boss who dispenses extra mines into the level.
* Can be deployed in ''VideoGame/{{Harpoon}}''.
* ''VideoGame/InTheHunt'' has ''loads'' of these in the first stage and the final stage.
* In ''VideoGame/SteelSaviour'', the first MiniBoss drops these near you, which explode in a large SphereOfDestruction.
* Franchise/{{Pokemon}}:
** Koffing's appearance is based on a floating naval mine. Since it learns [[TakingYouWithMe Self-Destruct and Explosion]], this is fitting.
** Qwilfish (along with its Hisuian form and Overqwil) also resembles a navel mine and the fact that its part Water type sells its motif.
* ''VideoGame/Sly3HonorAmongThieves'' features these as a hazard in some stages, as smallish items (often with their own inner tubes for flotation). The last chapter notes your approach to magnetic mines in a ship. [[spoiler:The Cooper Gang avoided CriticalExistenceFailure by bringing the ship from the prior chapter. Made primarily of wood.]]
* Relic Entertainment's VanityPlate shows one of these.
* ''VideoGame/{{Crysis}}'' had them for some reason.
* Appeared in one mission in ''VideoGame/GrandTheftAutoChinatownWars''.
* You can find the gargantuan red and black [[http://borderlands.wikia.com/wiki/Lance_Mine Lance mines]] scattered around in ''VideoGame/{{Borderlands}}: The Secret Armory of General Knoxx''. If you get too close, they will explode and automatically down you, and you can detonate them from afar with rockets and grenades.
* Common obstacles in the first two ''VideoGame/CrashBandicoot'' sequels.
* 2/3 of the underwater stages in ''VideoGame/Alundra2'' feature these, which explode if you touch them. Then there are the ones that that start following you.
* The SNES platformer ''VideoGame/{{Claymates}}'' had a few of these floating around some of the longer underwater sections.
* The RunAndGun game ''VideoGame/CTSpecialForces'' has naval mines in underwater missions that kills the player on contact. These can be shot from a distance however.
* ''VideoGame/DukeNukem3D'' features small mines in the "Toxic Dump" level.
* ''Sub Culture'' had whole fields of this, sometimes made extremely dense for some missions.
* The player's ship has to navigate minefields every now and then in the ''VideoGame/NavalOps'' series. You can also lay mines, but they don't do very much damage and getting another ship to run into them is iffy at best.
* ''Franchise/TheLegendOfZelda''
** ''VideoGame/TheLegendOfZeldaMajorasMask'': There are a few explosive mines in the waters of Pirate's Fortress in Great Bay. They're almost identical in appearance (spiked silver spheres) to the sentient Spikes that appeared in the Water Temple from ''Ocarina of Time'', only these mines are attached to chains so they don't float upward.
** ''VideoGame/TheLegendOfZeldaPhantomHourglass'': There are underwater enemies during the treasure-salvage minigames that evoke this look, being spiked balls with eyes that explode if you make contact with them with either the crane hook or the treasure chest you're salvaging [[note]]the chain linking the hook and the boat is, by necessity, non-interactive with the mines[[/note]].
* ''[[VideoGame/{{Richman}} Richman 4]]'' has landmines that look like one rather than actual landmines.
* ''VideoGame/KingdomOfLoathing'' has mine crabs, hermit crabs that claimed naval mines as their homes. See DemonicSpiders.
* ''VideoGame/{{Bug|1995}}'' had these in [[UnderTheSea Quaria]]. They blow up if you touched them, of course.
* Featured in the seventh story mission of ''VideoGame/JawsUnleashed''. Just touching the chains which the mines are attached to will make them explode.
* The first Venice level in ''VideoGame/TombRaiderII'' has a group of sea mines in by the level exit. Naturally, you couldn't drive your boat through the area unless you wanted to suicide but the trick to clearing the mines is to accelerate to the mines and jump out of the boat before impact.
* ''VideoGame/TombRaider2013'' picks up the tradition in one of the later areas, a stretch of beach [[DerelictGraveyard choked with shipwrecks]] from every era since the beginning of seafaring. The whole area is littered with about a dozen sea mines that look exactly as described at the top of the page. Some float in the sea, others lie half-buried in the sand, all of them are harmless [[TooDumbToLive unless you shoot at one while standing near it]]. Finding and detonating them all completes one of the area's challenges and rewards Lara a nice amount of ExperiencePoints.
* In ''VideoGame/BanjoTooie'', the Submarine Challenge minigame involves destroying a bunch of these (called Shrapnel) for points.
* Lots of them show up in ''VideoGame/GoldenEyeRogueAgent'' in a cutscene when you arrive at Crab Key.
* ''Franchise/SuperMarioBros'':
** Shows up in the game ''VideoGame/SuperMarioWorld''.
** They return in ''VideoGame/SuperMarioGalaxy2''. Like just about everything in the ''Mario'' games, they have eyes, and will try to lean into your path if you swim too close.
* ''VideoGame/AdvancedStrategicCommand'' has anti-ship and anti-sub mines. Standard unitsets include minelaying-capable submarines, among other things.
* From the ''Franchise/MegaMan'' series:
** ''VideoGame/MegaMan4'' has some stationary underwater mines that explode when you linger near them in Dive Man's level.
** ''VideoGame/MegaMan9'' has ones that look normal enough at a first glance, but when neared or shot at, [[ActionBomb they'll reveal their faces and chase you around briefly before exploding]].
* Certain environments had these in ''VideoGame/{{Carmageddon}}''. Interestingly enough, they frequently appeared above water as well, still floating while chained to the ground. If run into, the whole sprite would explode and deal dynamic but even damage to the recipient's vehicle based on his/her innate strength and armor level.
* A rare appearance of the "torpedo launch tube" type of modern sea mine is the Widow mine in ''VideoGame/{{Starcraft}} 2'', which burrows into the ground and periodically launches a single homing rocket.
* In keeping with the game's goofy, nonsensical 1960s setting, ''VideoGame/TeamFortress2'' features the [[http://wiki.teamfortress.com/wiki/Sentry_Buster Sentry Buster]] robot enemy in Mann Vs. Machine mode. It is half robot Demoman, half sea mine, and all ActionBomb.
* Chapter 4 of ''VideoGame/GatlingGears'' has these with a twist: TheEmpire has drained the entire sea, turning it into a desert, so the mines are stuck in the ground like landmines. There's also an achievement for not getting damaged by any of these.
* The ''VideoGame/{{Commandos}}'' series, particularly ''Men Of Courage'', has them. The Diver has to disarm them in at least one mission.
* Somewhat ironically, sea mines end up as land mines in ''VideoGame/MechWarrior 3'', where you were tasked with infiltrating a former lake for one mission. The heavy sea mines that had been placed there to ward off a naval attack did not escape the lake when it drained and dried up, and instead sank into the sediment on the bottom, becoming a hazard to any large, passing pieces of metal, such as your HumongousMecha. This obligates you have a sense for careful navigation, a watchful eye, and an equally steady hand to locate and destroy the mines with neither radar alerts nor targeting assistance.
* A few missions in ''VideoGame/CobraTriangle'' have you disposing of mines in safe zones. If your boat gets too close to one as it goes off, you'll lose a life.
* The mines in ''VideoGame/{{Minesweeper}}'' resemble the typical spiked sea mines.
* Both ''VideoGame/FeedingFrenzy'' games have sea mines as hazards the fishes have to avoid. Should one touch it and BOOM! They can also be quite useful, as predators, too, go BOOM when hitting one.
* In ''VideoGame/DonkeyKongCountryTropicalFreeze'', some naval mines can be found in ''Irate Eight''. They are set off when Donkey Kong swims near them and blast four pieces of shrapnel when exploding.
* When underwater in ''VideoGame/SunlessSea'', the player can encounter submerged sea mines. Running a Zubmariner into it is a ''very'' bad idea. There are also the Unexploded Unclear Bombs, which have a red glowing dot at their center (just like the one featured on the main menu) and can be disarmed.
* ''Videogame/FallenLondon'', its sister game, has the Unexploded Mine as a weapon. It doesn't actually make you more Dangerous, however, but rather more ''Persuasive''. As it turns out, plopping an armed mine strong enough to sink battleships right on the table before beginning negotiations [[WeaponForIntimidation strengthens your position significantly]].
* During ''VideoGame/{{Octogeddon}}'''s {{Bonus Stage}}s, the animal buddies must dodge a plethora of sea mines descending upon them at high speeds.
* In one level of ''VideoGame/HalfLife2'', you zip through the river on a motorboat while an enemy chopper drops mines in front of you.
* Sea mines appear in ''VideoGame/{{Warframe}}'' as obstacles in Grineer {{underwater base}}s that explode when you approach them, likely killing you in one hit. They are bright red so you can easily shoot them from afar without risking yourself.
* Some underwater areas in ''VideoGame/MonsterBoyAndTheCursedKingdom'' are loaded with sea mines, some of which start off anchored to the floor and rise up when a crab cuts the rope.
* They appear as a hazard in ''VideoGame/CommanderKeen'' 4's underwater level, moving back and forth or up and down.
* In ''[[VideoGame/BloonsTowerDefense Bloons TD 6]]'', Admiral Brickell passively deploys sea mines around nearby water that seek and blow up on approaching bloons. Her level 10 ability drops a gigantic sea mine on any body of water. There's also the MOAB Mine, which is shaped like a sea mine, but it can be dropped on land.
* ''{{VideoGame/Sipho}}'': Fittingly for a game that happen entirely within liquid environments, the poison bombs created by the Miner zooid are orbs with glowing protrusions that resemble a naval mine.
[[/folder]]

[[folder:Webcomics]]
* ''Webcomic/{{Newshounds}}'' featured a dolphin whose former job was to find these. He wasn't very good at it. Favourite line: 'Boom boom boom go the ocean zits!'
[[/folder]]

[[folder: Web Video]]
* ''WebVideo/WorldWarTwo'': The series covers the mining of the seas by Allies and Axis. Early episodes tell the story of mysterious new German mines wreaking havoc on British shipping before they were discovered to be magnetically triggered and a degaussing countermeasure developed.
[[/folder]]

[[folder:Western Animation]]
* The unfortunately-named "Stink 'n' sink" mines from ''WesternAnimation/AvatarTheLastAirbender,'' invented by Hakoda.
* On ''WesternAnimation/{{Centurions}}'', Max Ray's Depth Charger weapon system was equipped with one called a "hydromine". He once used several of them to stop a tsunami from occurring when a massive meteorite landed in the ocean.
* On the ''WesternAnimation/LooneyTunes'' short "Porky's Snooze Reel", a jellyfish swallows a mine whole, despite the narrator's warnings, and is blown into jars of Jell-O.
* ''WesternAnimation/TotalDrama'':
** For he last part of the race in "[[Recap/TotalDramaPlanesTrainsAndHotAirMobiles Planes, Trains, and Hot Air Mobiles]]", the final three have to get from Tijuana to Hawai with boats. Among the obstacles en route are sea mined. Heather and Cody evade them, while Alejandro drives over one and goes flying, only to land back down to tie with Cody for second place.
** The second part of the challenge in "[[Recap/TotalDramaBackstabbersAhoy Backstabbers Ahoy!]]" is for the two teams to get in boats and trigger a total of three sea mines between them. To do it safely, each boat is equipped with a mounted gun with which to shoot the bells atop the bombs that when rung bring about the explosion, but any means to activate the bombs are allowed. The Toxic Rats claim the first bomb when Scott shoots it. The Mutant Maggots claim the second bomb courtesy of Svetlana's unparalleled acrobatics. After that, the Mutant Maggots crash and Jo settles victory for the team by throwing Cameron onto the last bomb.
[[/folder]]

[[folder:RealLife]]
* The spiky protrusions on classic sea mines are so-called "Hertz horns". They are lead horns which contain a small glass ampulla full of electrolyte and two electrodes. When a ship runs into the mine, the soft lead of the horn will bend, breaking the ampulla and letting the electrolyte run in the horn. It will then close an electric circuit, which then in turn will detonate the fuse and the explosive charge in the mine itself.
* Maritime mine warfare is actually OlderThanTheyThink: the concept was first introduced in the Ming dynasty China in the 14th century, and used against Japanese pirates (Wako) in the 16th century.
* Mines are a menace at shallow and narrow seas. Consequently, littoral countries with vast archipelago or shallow coasts are experts on mine warfare. Examples contain Finland, Greece, Germany, Thailand and Poland. Conversely, they are of little use on depths more than 200 m.
* Finland literally bagged the Soviet Baltic Fleet at Kronstadt harbour in 1941 by mining the whole Gulf of Finland. The minefields contained mines on different depth so that not even submarines could get out. After the Armistice 1944, openings were cleared on the minefields so that the Soviet ships could freely enter and exit the Baltic. The minesweeping continued well into the 1950s.
* Sea Mines, like their land-based cousins, could serve as more of a deterrent than a direct weapon. Enemy ships had to sail around known minefields, thus a force could mine waters on the most direct route between an enemy base and their own waterways. Such a tactic was used during UsefulNotes/WorldWarI to try and limit the effectiveness of German U-Boats by forcing them to take a longer route to get at Allied shipping with the North Sea Mine Barrage. There is a famous saying from the Gulf War that you do not actually need any mines to create minefield: you just need a press release and a Notice to Mariners.
* As soon as UsefulNotes/{{Russia}} invaded UsefulNotes/{{Ukraine}} in February 2022, Ukrainians deployed mines along their country's South-West coasts of the Black Sea to prevent Russian landings (which happened on their coasts of the sea of Azov as part of the siege of Mariupol), especially around Odessa. Russian officials have [[NeverMyFault pretended that this was the cause of the grain embargo]], but in truth they were just blockading Odessa with the ships of their Black Sea fleet (besides, Russian minesweeping ships have been spotted by satellite imagery in said zones, and Russians even have dropped mines of their own).
[[/folder]]
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