Bowser's Castle (also known as Bowser's Keep in Super Mario RPG: Legend of the Seven Stars, Bowser Castle in Mario & Luigi: Bowser's Inside Story, or Castle Koopa, and Neon Castle in the Mario cartoons) is Bowser's domicile and the base of operations for the Koopa Troop. Bowser has a variety of different castles throughout the Mushroom World, each of which usually functions as an important base from which the Koopa King formulates his plans. Bowser's Castle is usually the final area that Mario visits to defeat Bowser and rescue Princess Peach, and is usually guarded by Bowser's most powerful minions.
 Super Mario series
 Super Mario Bros. / Super Mario Bros.: The Lost Levels
Bowser's Castle first appears in Super Mario Bros. at the end of World 8. In the level 8-3, Mario battles Bowser's forces outside of the castle, which can be seen in the background; in World 8-4, Mario ventures into the castle itself, where he battles and defeats Bowser in order to save Princess Peach. It is similar in Super Mario Bros.: The Lost Levels, except that it appears in world D-3 and D-4 instead, while a castle located in the sky is found in World 8-4.
 Super Mario Bros. 3
In Super Mario Bros. 3, Bowser's Castle (as well as Bowser himself) is not seen until the very end of the Dark Land. The mentioned castle is one of the longest levels in the game. Bowser is fought at the end of the castle, and Princess Peach is freed. The map icon was modified in Super Mario Advance 4: Super Mario Bros. 3 so that it is animated.
 Super Mario World
In Super Mario World, Bowser's Castle is found in the Valley of Bowser. There are two ways of entering the castle, and many ways to reach the end of the level. There are two main corridors where Mario or Luigi will have to choose one of four possible doors. The player can also reach the Castle by using the Star Road that leads them to the front gate, bypassing the rest of the Valley of Bowser entirely. To get to the back gate, the player had to find the secondary exit in Valley of Bowser 2 and go through Valley Fortress. This takes the player straight to Back Door, skipping most of the level.
 New Super Mario Bros.
In New Super Mario Bros., Bowser's Castle is relatively similar-looking to the one in Super Mario World. It is found rising out of a lake of lava and is at the end of a twelve-level-long path. Once inside, Mario and Luigi will encounter Thwomps, Dry Bones, Rocket Engines, as well as Podoboos. The ? Switches in the castle have an unusual effect; once pressed, the room (or at least the gravity of the room) will flip upside down (including the player, enemies and items). The second part of the castle is a looping room, similar to Worlds 4-4 and 7-4 of Super Mario Bros., with lots of lava, a single Podoboo, and a single Firebar. Once the final boss door is reached at the castle's end, the Player will have to battle both Bowser Jr. and Bowser.
 New Super Mario Bros. Wii
Bowser is again fought in his castle in New Super Mario Bros. Wii. The characters go through three parts: The first is a normal side-scrolling area with lava, Podoboos, and Firebars. The second part is a vertical area with draining lava which auto-scrolls downwards, more Firebars and some Dry Bones trying to stop Mario. The third is Bowser's lair. In the final battle, Kamek casts a spell to make the Bowser grow massive, and he chases Mario and the rest of the characters through his castle.
Later after the final battle, Bowser, Bowser Jr., and the Koopalings are flattened by the castle as it falls over.
 Super Mario 3D Land
Bowser has two castles in Super Mario 3D Land, both located in the eighth world. The first castle is the World 8 Castle, its appearance is similar to castles of previous titles, as well as previous castle levels in the game. At the end of the castle Mario fights Bowser and defeats him by pressing the switch at the end of the bridge, causing Bowser to sink in the lava below. Mario makes his way to Peach (which can previously be seen in the level using a pair of binoculars), only to discover it's just a cardboard cutout. Bowser then appears with the REAL Peach in hand, and flees to his larger castle, which is the true Bowser's Castle.
The real Bowser's Castle differs from previous castle levels, as Mario spends much of it riding Bonecoasters. Mario then reaches a cannon which launches him to a tower with another cannon on it, which Mario uses to reach Bowser's tower. Mario then walks to the big red door and enters. Peach is tied to the flagpole, but before Mario can rescue her, Bowser falls from above and attempts to crush Mario, which causes the floor to collapse, and the final battle begins. Bowser attacks Mario with fireballs, spiked balls, and barrels as Mario makes his way up the castle until they reach the second bridge. Mario tricks Bowser into clearing the path to the switch, which Mario presses, causing the bridge to collapse and Bowser to fall. However, as Mario continues to make his way up the castle, Bowser returns and pursues Mario, breathing purple flames which jet towards Mario, until they reach the final bridge, in which Bowser chases Mario until Mario reaches the final switch, which he presses, once again causing the bridge to explode, sending Bowser falling into the lava. Mario then rescues Peach and they head back home.
After completing the Special Worlds, Bowser kidnaps Peach again, and Mario must return to his castle to defeat him and save Peach once again.
 New Super Mario Bros. 2
 DIC Cartoons
 The Super Mario Bros. Super Show!
In The Super Mario Bros. Super Show!, King Koopa owns a wide range of castles, ranging from fortresses, towers and even an ice palace; most often at the end of an episode, the featured castle of King Koopa would be destroyed, and if not, would likely not be seen again. Unlike the games, the various castles seen in The Super Mario Bros. Super Show! lack the abundance of traps that would normally appear in a castle owned by Bowser.
 The Adventures of Super Mario Bros. 3
The Adventures of Super Mario Bros. 3 migrates away from the concept of King Koopa owning several castles and, instead, he only owns one castle, located in Dark Land. This castle is referred by the name "Castle Koopa" and "Koopa Castle". Castle Koopa largely resembles its game counterpart, with Bowser's image engraved on it, though it's blue in color and lacks towers. Castle Koopa also possesses a large hall filled with portraits, as well as bedrooms for the Koopalings and a laboratory most often used by Kooky von Koopa.
 Super Mario World television series
In Super Mario World, Neon Castle is featured as the main base and home for Bowser and the Koopalings. Apparently located in a lava filled wasteland, Neon Castle lack the amount of towers its game counterpart possesses, only having one; Neon Castle also possesses a rectangular shape and, like the Japanese version of Super Mario World, has "KOOPA" flashing in neon lights on its front, instead of "BOWSER". Like its game counterpart, Neon Castle possesses a large amount of traps, such as Ball 'n' Chains, lava, fire-breathing statues, as well as various kinds of minions. In the episode Mama Luigi, Mario refers to it as Bowser's "Coney Island Disco Palace".
 Mario Is Missing!
Bowser's Castle is the main setting of the game Mario Is Missing!, but instead of being located in the Koopa Kingdom, like in the other games, this castle is located in Antarctica. The castle is also the main setting for the game Mario's Time Machine, except this time it's located in an unknown area.
 Super Mario Adventures
In Super Mario Adventures, Bowser's Castle is only seen near the end of the comic, and is portrayed as a large fortress, having many spike-covered towers and a large great hall, capable of holding several hundred different creatures. Catacombs and a lava filled chamber inhabited by Blarggs are also depicted in this version of Bowser's Castle.
 Mario Kart series
Bowser's Castle has appeared in every Mario Kart game to date. In Super Mario Kart, there is a different course of the castle in every Cup except the Special Cup. Bowser Castle 1 appears in the Mushroom Cup, Bowser Castle 2 appears in the Flower Cup, and Bowser Castle 3 in the Star Cup. Mario Kart: Super Circuit features all of the courses from Super Mario Kart, so they appear in that game as well. Also the Paper Mario castle makes a cameo appearance in the Rainbow Road track. Mario Kart 64 features a Bowser's Castle course in the Star Cup. In 50cc mode, there is one Thwomp, in 100cc mode, there are two, and in 150cc and Extra modes, there are three Thwomps right before turn 4. Mario Kart: Super Circuit has its own Bowser's Castle courses, but it also has a fourth one. Mario Kart: Double Dash!! and the later games of the series have a Bowser Castle course in the Special Cup. It also features Bowser Castle 2 from Mario Kart: Super Circuit (Banana Cup section) in Mario Kart DS, the same Bowser Castle from Mario Kart 64 (Lightning Cup) and Bowser Castle 3 from Mario Kart: Super Circuit (Leaf Cup section) in Mario Kart Wii and Bowser Castle 1 from Mario Kart: Super Circuit (Shell Cup section) in Mario Kart 7 as the retro courses. Every version of the course features the same dangers: lava, Thwomps, and dangerous jumps.
 Yoshi series
 Yoshi's Safari
 Super Mario World 2: Yoshi's Island
In Super Mario World 2: Yoshi's Island and its remake Yoshi's Island: Super Mario Advance 3, Bowser's Castle is located atop a tall mountain on the island. The last level takes place here, and it requires the player to go into one of four random doors. Afterward, a giant playroom for Baby Bowser is discovered inside. After defeating Baby Bowser, Kamek will come by and make him extremely large. The player fights on the top of the castle which, throughout the battle, is slowly destroyed. The castle is later entirely destroyed after the final battle.
 Yoshi's Story
In Yoshi's Story, Baby Bowser's Castle is split into four different areas: Mecha Castle, Lift Castle, Ghost Castle, and Magma Castle. No matter what part of the castle Yoshi decides to go to, he will always meet up with Baby Bowser. The outside of the castle will also be seen whenever one of the Yoshis gets defeated, captured, and brought to the castle, along with when White Shy Guy retrieves one. It is also seen in the ending sequence when Baby Bowser's minions carry him away.
 Yoshi's Island DS
In Yoshi's Island DS, Bowser travels back to the past searching for the seven Star Children so he could rule the universe. He takes over the castle of his younger self. After Baby Bowser is defeated, Bowser himself is faced. When he is defeated the first time, Kamek makes Bowser gigantic and destroys the castle in the battle.
 Super Mario RPG: Legend of the Seven Stars
During the events of Super Mario RPG: Legend of the Seven Stars, Bowser's Keep is isolated on a mountain of red, jagged rocks. The keep rests on the largest rock, which, in fact, resembles Bowser himself. The castle can only be accessed by a long bridge that connects to the faraway Vista Hill. The halls of Bowser's Keep are lined with statues of Hammer Brothers and Bowser. The castle is originally guarded by Terrapin soldiers. Additionally, molten lava flows through the keep in several areas. Fortunately, several bridges allow access across the lava. Unfortunately, the bridges are wooden, and as such, will eventually collapse in a room filled with lava. In fact, one bridge breaks right after Mario walks across it. Later, this bridge is replaced with hovering Donut Blocks. The castle is also filled with ornate chandeliers. Mario and Bowser actually duel on the top of these chandeliers.
Bowser's Keep is also the Smithy Gang's base of operations on Mushroom World. During the beginning of Smithy's invasion, the gigantic sword Exor crashes into the keep. Since Exor is the gateway to Smithy's dimension, the soldiers of the Smithy Gang have an easy time taking control of the castle. In fact, many of Bowser's soldiers defect or run away instead of fighting. Eventually, the Smithy Gang claims the castle as their own. Additionally, Exor destroys the bridge connecting Bowser's Keep to the outside world. As such, the castle can only be accessed by flying vehicles.
Before the fight against Magikoopa, there will be 6 doors to choose from, though only 4 doors are required. There are 2 action courses, 2 battle courses, and 2 puzzle courses.
 Paper Mario series
 Paper Mario
In Paper Mario, a new Bowser's Castle is secretly built right underneath Princess Peach's Castle, and Bowser lifts it into the sky, kidnapping Princess Peach, along with her castle. The power used to lift the whole castle into the sky is the Star Spirits' and the Star Rod's power, both of which Bowser had stolen from Star Haven. In the end, Mario manages to take back the Star Rod and destroy Bowser's Castle while saving Princess Peach (and her castle). In this game, Bowser's Castle looks bigger than Peach's.
 Paper Mario: The Thousand-Year Door
In Paper Mario: The Thousand-Year Door, Bowser's Castle doesn't play a major role, as only the outside and a hallway are seen. Its appearance is mainly to show Kammy Koopa explaining to Bowser what happened to the Princess.
 Super Paper Mario
In Super Paper Mario, the castle has an equally minimal role, as it is where Count Bleck kidnaps the entire Koopa Clan, and Tippi takes Mario to Flipside. This is the exact same castle seen in Paper Mario: The Thousand-Year Door. However, in The Bitlands, Bowser found a set of several smaller castles, where several of his minions were located. After Mario destroyed them, and defeated the Koopa King, the Princess convinced him to join them on their quest.
 Paper Mario: Sticker Star
Like in the first Paper Mario, Bowser's castle is the final area in Paper Mario: Sticker Star. It was initially disguised as a cliffhead. However, after Mario collected all of the Royal Stickers, he managed to reveal via paperization the true form of the cliff. Nonetheless, Bowser had his castle levitated to the sky as a means to deter Mario's advance on it shortly thereafter, although he nonetheless managed to arrive there via a Flutter that Mario befriended. Mario later fought and vanquished Kamek in this castle, and later defeated Bowser (who was currently using the sixth Royal Sticker after he accidentially obtained it).
 Mario & Luigi series
 Mario & Luigi: Superstar Saga
In Mario & Luigi: Superstar Saga, Bowletta uses Bowser's Castle to attack the Beanbean Kingdom. This castle can fly, breathe fire, and it looks like a statue of Bowser. On the castle's "hands" there are tower tops. Mario, Luigi, and Prince Peasley go there with Blablanadon near the end of the game to stop Bowletta. The castle is the final world of the game. In the castle, the Mario Bros. have to get through many challenges and fight each of the Koopalings (some with Time Bob-ombs) in their room in order to open the next area until they make it to Fawful. After the fight, the Mario Bros. get to the throne room where Bowletta resided. They fought Bowletta, but she then swallows the Bros., making them fight Cackletta's spirit inside Bowletta's stomach. After the Mario Bros., Peasley, and Blablanadon escape the castle, a time bomb planted by Prince Peasley blows the castle up, and the remains crash into the Oho Ocean. This flying castle design is reused in Yoshi's Island DS, and is somewhat similar to the one featured in Paper Mario.
The ground version of Bowser's Castle appears in the credits, when the Toad Express drops the present through its roof.
 Mario & Luigi: Partners in Time
In Mario & Luigi: Partners in Time, the castle is called Baby Bowser's Castle, since the Mario Bros. visit it in the past. The four heroes get to see a little of Baby Bowser's castle. The four Bros. practically reunite and start their adventure together there. Baby Bowser is never seen inside the castle during the entire game. There is also a Time Hole here which links to Peach's Castle in the present. Oddly, the castle on the map in the presents looks exactly the same as the one in the past, so it still looks like Baby Bowser.
 Mario & Luigi: Bowser's Inside Story
In Mario & Luigi: Bowser's Inside Story, Bowser Castle is taken over by Fawful. Control of operating the castle is given to Midbus. After Bowser helps to fire a Banzai Bill at his own castle (taken over by this time), Midbus commands the castle to elevate, dogding the Banzai Bill and then to land on top of Bowser. Mario and Luigi must travel to Bowser's adrenaline gland and cause Bowser to grow big enough to fight his castle. In battle, the Castle's main attack is a flying ram. Its main tactic is opening its entrance doors and releasing Spinies, which prevent Bowser from punching. After the castle is in ruin, Midbus retreats and the castle is moved back to its original resting place. Later, Bowser attempts to gain access to the castle, however Midbus commands it to hover out of Bowser's reach. After wandering to the opposite side of the area, Midbus fires a giant cannonball at Bowser, who after building up energy courtesy to Mario and Luigi, throws it back at the castle, damaging it badly enough to force it to land. Bowser then gains access to his castle, where he discovers that not only had Fawful brainwashed his minions, but had also turned the castle into a theater. In the meantime, Bowser decides to see the show Fawful puts on. Fawful had, however, tricked him into a VIP chair, which fires Bowser onto the stage, getting him stuck in a forced fight against Midbus.
After Bowser beats Midbus, Bowser is forced to eat a "victory feast" that Boos feed him. Later, he gets so fat from all his force-fed food that he gets stuck in the floor. After a strange hand grabs Princess Peach, Bowser falls through the floor, lands on a treadmill, and catches on fire. Then, Bowser gets thrown into the Tunnel by lit up Bob-ombs.
Later in the game, Bowser must return here to look for the second Star Cure, which he had stolen before the events of the game. However, Fawful had blocked up the path to his treasure stash and Bowser must push a Fawful statue off the castle balcony to break the barrier. However, his former minions begin to push against the statue too, trying to save the statue and push Bowser off the balcony. Mario and Luigi then must help Bowser push the statue. finally Bowser manages to go underground and get to his treasure vault, but the Monty Moles that had helped Bowser get to underground Toad Town earlier are now working for Fawful, and are moving all of the treasure from the vault in the Fawful Express.
 Mario Pinball Land
Bowser's Castle is the last place Mario has to go in Mario Pinball Land. After using the Star Keys to open the gate, Mario goes into the main foyer (where another Air Cannon and Toad's Tent was located). Players have the option to explore the other rooms in the castle, where Mario will end up fighting all the bosses again (after clearing the room of the other nasties), or go through the Star Door in the middle of the foyer and face Bowser. Bowser's arena is quite small, as all the other levels are, but the Koopa King himself proves to be quite tricky. Bowser wanders around the room until he finds a spot to jump on. His landing causes the flippers to get stuck for a few seconds, rendering Mario vulnerable to be sent out. Every time Mario hits Bowser while walking causes him to rebound to another part of the room. Hitting Bowser while standing stops him from doing his jump. The only way to injure Bowser, however, is to spin the gears on the wall to raise the chained Thwomps upward, and then hit the ! Switch in the back of the room. This makes the Thwomps fall on the ground, causing Bowser to fall backwards, leaving Mario to bash him. Mario does this three times, but instead of beating him, Bowser curls up, acting like a giant pinball. It's then the flipper's job to keep Mario from falling out while bashing Bowser into the wall enough to send him flying out of the castle. This leaves Mario saving Princess Peach, and they both go back to The Fun Fair to enjoy the rest of the day.
 Super Princess Peach
As Super Princess Peach takes place on Vibe Island, rather than the Mushroom Kingdom, the castle itself is not seen during the events of the game. However, Bowser built a villa there, which is considered to be another castle.
 Mario Hoops 3-on-3
Bowser's Castle appears as a basketball court in Mario Hoops 3-on-3. The court has lots of dangers, such as Thwomps occasionally appearing out of ? Panels. Also, Podoboos launch up from the lava, and if any players touch them, they run around uncontrollably and on fire. Bombs do the same as well, but these ones are bigger. The music heard in this court is a remix of the Bowser's Castle theme from Super Mario Bros..
 Fortune Street series
 Itadaki Street DS
Bowser's Castle also appears as a stage in Itadaki Street DS, along with other stages from the Mario and Dragon Quest series. This Bowser's Castle is based on the one from New Super Mario Bros.. Players have to compete against Peach, Jessica and Bowser and place first to beat the board. Beating the board unlocks Bowser and Bowser's Castle.
 Fortune Street
Bowser's Castle appears in the Itadaki Street DS sequel Fortune Street as an unlockable board map. Its appearance is similar to that of the previous game. There are doors on the top of the bigger section of land and one on the very top of the smaller section of land. The players can use these doors to navigate through the board. The doors bring players to the same spot each time they go through them. In Tour mode, the player has to play against Peach, Stella, and Bowser while also coming in first to beat the board and unlock a new one.
 Mario & Sonic series
Bowser's Castle appears in Mario & Sonic at the Olympic Winter Games as a location in Dream Ice Hockey. It also appears in Dream Figure Skating as the second stage to be faced. It consists of a giant stone Bowser head. There is also a lot of lava around the dream event.
 Mario Sports Mix
Bowser's Castle is one of the fourteen courts of Mario Sports Mix and appears in all of the sports for the players to compete in. In volleyball and dodgeball, there are Podoboos which spring from the court, and the limit of the two camps can displace which advantages one team has compared to the other one. In basketball, it is the same except for the absence of limits in the court. For Dodgeball, when players get knocked out, the center line will shift so that the losing team has more room to work with. For Volleyball, the leading team gets more room, but the losing team will be safe from all Podoboos; the Podoboos will pop up at the center of the Volleyball court.
 Mario Tennis Open
Bowser's Castle returns as a tennis court in the game Mario Tennis Open for the Nintendo 3DS. It is a stone court built over a boiling lava landscape. Mecha Koopas can be seen on the sidelines as spectators. A refereeing Toad is seen sitting in a cage outside the castle itself, where the normal referee's throne is. This court is where the Shell Cup takes place in Tournament mode. The music for this court is a remixed version of Bowser's theme from Super Mario 64 and the Bowser Battle theme from Super Mario 3D Land.
"Bowser's fiery court built on boiling magma."
 Area Tattles
 Mario & Luigi: Partners in Time Maps
 Names in Other Languages