Blue Hell

Blue Hell (also known as the Abyss or the Underworld) is the name given by the player community to the large, empty area underneath the map's terrain in all three-dimensional (that is, those with 3D or HD graphics) Grand Theft Auto games. The name first started from Grand Theft Auto III in which the area underneath the landmass is usually blue. The color of Blue Hell usually depends on the time of day; It is usually either blue or grey during the day, but at night, it is dark grey.

Blue Hell can be described as a large, undefined area beneath the landmass, and almost every open-world 3-dimensional videogame has some sort of empty area underneath its terrain, so the game does not draw polygons where they cannot be seen. The player is not supposed to access Blue Hell, but several game glitches (including 'holes' or 'seams' in the world terrain) can result in the player ending up there. When the player falls into Blue Hell, they will fall for a few seconds before being teleported to the nearest pedestrian pathway (or vehicular if the player is in a vehicle). This is intentional, and was made by game developers so that if the player accidentally enters Blue Hell, they won't fall indefinitely. The Grand Theft Auto: San Andreas Blue Hell is the easiest to access and explore with the use of the in-game Jetpack.

Blue Hell is quite often confused with the Hidden Interiors Universe, which is another secret, normally inaccessible area within the GTA San Andreas game world.

Grand Theft Auto III

 * Going eastwards up the sloped alleyway in Saint Mark's, north of Marco's Bistro on Portland. The wall at the end of the backyards on the left hand side is not solid and the player can easily fall through it. After a few seconds in Blue Hell, the player will land in the middle of the main road just to the east of where they were.
 * Just outside the fence of the docks in Portland (near the trailers), there is a section of grass that is not solid. The player can fall through and will be put on the sidewalk nearby.
 * In the Staunton Island LCPD Station, one of the higher walls is not solid. The player can easily enter and fall into Blue Hell. After the fall, the player will land in front of the station's car park entrance.
 * If the player rides on the subway and enters one of the trains at the second door of the first car, and then exits the train at Francis International Airport, they may appear above the station, stuck inside the ceiling. Walking above the tracks (the player have to jump over one of the first support structures in the ceiling of the tunnel, otherwise the player will fall off the roof) and off them will make the player fall into Blue Hell and reappear at Francis International Airport. This is a good method to reach the whole Shoreside Vale without cheats or mods, if one didn't unlock it (however if the player dies or get busted there, the player will appear at the hospital/police station on the nearest island that the player has unlocked). Alternatively, the player may decide to walk across the tunnel (tested on PC and iPad version).
 * There is a section of rock on the northeast side of the Staunton Island coast that can be sailed through on a boat into blue hell. There is enough water modeled beneath the island to prevent immediately falling through blue hell and respawning; however, the water does not continue under the whole of the island, and sailing off of it will result in a fall and respawn. Depending on speed & direction, the player (and boat) may respawn in the Shoreside Vale portion of the Porter Tunnel. This is a relatively safe & reliable way of accessing Shoreside Vale as soon as boats become available.
 * On the Newport/Fort Staunton Expressway under the Callahan Bridge on Staunton Island, there is a corner that is unsolid. If the player goes into it, they will fall into Blue Hell and respawn on the sidewalk under Callahan Bridge.
 * On Staunton Island, some sections of the Liberty Memorial Coliseum are unsolid, and if the player manages to get into a hole, they will fall into Blue Hell and respawn on the nearest street.
 * At Joey's Garage on Portland, if the player does the "Accessible Joey's Garage-glitch", one of the walls isn't solid. If the player goes through it, they will fall into Blue Hell and respawn on the street.
 * At Ghost Town, there's a large Blue Hell entrance where the half of the town is situated.
 * At the outer left side of Francis International Airport's Porter Tunnel entrance, a low barrier intersects with the outer side of the tunnel. Running between these two will take the player behind the tunnel walls with a hole leading to Blue Hell nearby. Falling into the hole will result in the player respawning at the sidewalk across the airport's terminal.
 * At the glass building of Carson General Hospital, there is an unsolid area on the wall. If the player manages to get there, they will fall into Blue Hell and respawn on the sidewalk below.
 * If the player somehow sees the space at the autocrusher in Harwood Autocrusher and Junkyard, they will notice that the car is crushed using a script, therefore allowing them to see blue hell.

Grand Theft Auto: Vice City

 * If, when playing the PS2 version, the PS2 is unable to load or have problems loading, the ground might not be loaded and the player will fall into Blue Hell and spawn on land a few seconds later. Alternatively, the ground may become untextured and the game will freeze.
 * If the player somehow reaches the top of buildings past the game's height limit, they may see a large hole instead of a roof. This acts as an entrance to Blue Hell.
 * Another Blue Hell is located at the Vice City Police Department in Washington Beach.
 * In the PS2 version, its possible to enter Blue Hell by flying a helicopter into an in-door pool located in the rear side of the Vercetti Estate, if the player flies up through the pool's ceiling and drop back down, he/she will be able to fly underneath the game world's terrain.

Grand Theft Auto: San Andreas

 * In Esplanade North, San Fierro, the player will see several docks jutting out into the San Fierro Bay with warehouses situated upon them. Next to one of these docks is a submarine called the USS Numnutz. If the player swims directly down from the submarine to the bottom of the waterway next to the dock, they will notice a greyish color which does not match the color or texture of the surrounding rock. This area is actually a hole that the player can swim through to enter Blue Hell.
 * If the player stands on top of a San Fierro tram and takes a picture with the camera while on the tram, CJ may fall into Blue Hell and after a few seconds, and eventually land on the sidewalk.
 * Also, in San Fierro, there is a large clothing store in Doherty, opposite the tract of wasteland. The top portion of the wall (between the top floor and roof) is not solid, and can be accessed with a jetpack.
 * Also, in the Doherty area specifically at the fire department you can notice a large texture glitch consisting of dirt and a large pit sitting above the firetruck around the back of the building. This is actually the hole you bury the foreman from Deconstruction in. For some reason it's been moved a little bit south of its original spot and if you go to that spot it's completely filled in with solid dirt textures. Going straight past the firetruck to the road that is slanted there is a blue hell portal falling through alone will kill you going falling with a vehicle will teleport CJ back on the ground near by. It also completely bugs out the crane at the construction site making it constantly spin. This has only been seen on mobile.


 * In Mulholland, Los Santos, there is a newspaper shop with a non-solid areas in the roof which will lead to the interior of the building, and from there to Blue Hell itself.
 * In the PS2 version, if one gets a jetpack, and then goes to the Mulholland Safehouse, on the empty pool, one of the corners is not solid. Walking through it will make the player fall underneath Los Santos. The player can use the jetpack to explore the city via the "underground". Otherwise, if one walks through the unsolid wall without a jetpack, he/she may fall for a while and respawn in a street.
 * At Las Venturas Airport, one of the walls of the main building has a glitch wherein running at it enough will pop the player through into Blue Hell. The wall is located where the fence around the runway meets the building.
 * Also in Las Venturas, there is an unmarked Pay 'n' Spray east of the casino in the Come-A-Lot district. The southwest corner of the Pay 'n' Spray is not solid; if the player enters that spot via jetpack and lets Carl Johnson sink into the hole for a while, he will fall into Blue Hell, later automatically spawning on the sidewalk outside the Pay 'n' Spray.
 * The player can use Blue Hell to re-enter the Area 69 interior after the Black Project mission. It should be noted that some sections of it are non-solid, however.
 * Sometimes after the mission End of the Line, the interior of Big Smoke's Crack Palace will disappear, however the wall will not repair itself. This creates a large hole to Blue Hell.
 * If the player goes far out enough into the ocean and swim to the bottom of it, the ocean floor is not solid, so the player will fall into Blue Hell and respawn somewhere in San Andreas.
 * There is a building in Juniper Hill, San Fierro, in which one spot on a wall is not solid, but can only be accessed with a jetpack. It leads to the interior of the building, and then to Blue Hell. The building is between a clothing store and a safe house.
 * Also in Dillimore, Red County, there is a Discount Furniture store. Its name is not shown on the shop, but it is a building with a lot of signs and stickers on the windows. It's not an enterable building, so there will be no yellow marker at the entrance, but go to the entrance with a jetpack, and fly up, and the roof will not be solid. Then just try to get in.
 * If one spawns a vehicle with the driver's door in a wall (so that the vehicle is partially immersed in it), and gets into it, and then exits it, CJ may exit on the driver's side. Since the door was inside the wall, CJ will now be inside of it as well and will fall to Blue Hell before respawning on the nearest street.
 * In Tierra Robada, below the Robada Intersection and between the Garver Bridge and the Kincaid Bridge, there is a section of unsolid terrain along the small cliff side above the sea. One may obtain a Jetpack and fly downwards against the section for a while, and pretty soon, CJ will be popped into Blue Hell.
 * In Bayside Tunnel, specifically the north tunnel, there is an unsolid section of wall inside the west side of tunnel entrance. One must obtain a jetpack and fly 'into' the wall and be popped to the blue hell.
 * There is a tall rock somewhere in the roads of Flint County. The player will need a fast vehicle to enter blue hell via the rock. The player must make sure he/she drives very fast, or it will not work. If it works, the player will fall down into Blue Hell and respawn in Back O Beyond.
 * In Temple, Los Santos, in front of a tall building, one may climb a vehicle to the stairs, turn left and drive to a right-most part of the wall. This can be only accessed with small vehicles.
 * Near the Bike School in Las Venturas, it is possible to find an empty lot used for the school's tests. One of the corners of this lot is not solid, and when walked through, it will lead to the Blue Hell. One can also distinguish the location by looking for the Kart that spawns right next to it.

Grand Theft Auto: Liberty City Stories

 * Near the hospital in Staunton Island is a small construction site where the player can find a ramp and jump to a platform above the hospital. The player can go inside the glass of the hospital windows in a corner and will fall into a tunnel (the same tunnel seen during the mission Bringing the House Down). During the mission, the Blue Hell under Fort Staunton is solid so the player won't fall through. See Carson General Hospital for a full description.
 * On Staunton Island, some sections of the Liberty Memorial Coliseum are unsolid, and if the player manages to get into a hole, the player will fall into Blue Hell and respawn on the nearest street.
 * If the player manages to steal Faith's helicopter in the mission False Idols, the player can drive the helicopter above some buildings which don't have a roof. Get inside the roof and there will be a large hole which will lead to Blue Hell. The player can see the tunnel used in the mission Bringing The House Down, which can be found under the hospital in Rockford and many other things.

Grand Theft Auto: Vice City Stories

 * Go to the side of the Prawn Island bridge going to Vice City Mainland. Run onto the wall until falling into Blue Hell, and the player will respawn at Diaz's mansion.
 * The player can also enter Blue Hell by running towards a corner and a tank hits the player. This with cause the player to fall into Blue Hell and spawn at the nearest land 10 to 15 seconds later.
 * Use a vehicle and go to an invisible wall near the freighter in Viceport. Drive and bail out and swim to the invisible wall until finding a hole, then use the hole. The player will fall in the Blue Hell and reappear in the nearest land.
 * Fly a Skimmer to the Downtown-Prawn Island bridge (either InterGlobal Films or one of the mansions). Exit the Skimmer and walk until swimming. In the InterGlobal Films loop, swim all the way. The end of the route is at the road lanes between the three mansions and InterGlobal Films road.
 * If the player gets into the Easter Egg Building room with a Sanchez in the PlayStation 2 version of Vice City Stories  and pulls a wheelie in the top right corner, they will clip through the building and fall into Blue Hell.

Grand Theft Auto IV

 * Sometimes, when the player utilizes the Swingset Glitch with the Tudor swingset and a large truck like a Benson, Phantom or Yankee they may be thrown into Blue Hell for a few seconds and then back on the surface somewhere near the swing.
 * A trick some users do in multiplayer (in deathmatches and Free Mode) is fly a helicopter into the ground near the airport, and fly in Blue Hell, then come up in a hangar near where Annihilators spawn.
 * Part of the south side of the Rotterdam Tower (just beneath the first high ledge) is non-solid, and can be entered with a helicopter to access Blue Hell. From here, the player can enter interiors they could not enter before, go underwater, and explore some buildings. The player may accidentally re-enter the "real world", however, as some "real" interiors are not visible from Blue Hell (this is especially true of tunnels), and entering these will restore the player to the normal game world.
 * Upon entering the Schottler Medical Centre, turn right, and then right again. The player will be in a long hallway, with some windows and hospital privacy screen directly in front of them. Throw a grenade near the wall; this will shatter the windows and move the screens. The player can now jump through the window and walk around in Blue Hell with some of the hospital's decals, doors, even pedestrians invisible for a while, however, if venturing to far towards the street, the surroundings will reappear.
 * Driving east into the Booth Tunnel at high speed may put the player into Blue Hell for a few seconds.
 * Getting hit by a train underground while in a car may put the player into Blue Hell for a few seconds.
 * At Pier 45, facing the back from the water, swim to the left were there is a bunch of wooden posts. Climb on to one. Niko will jump over it as if it were a fence and land in "water". Swim around and he will fall into Blue Hell.
 * Near the West River helipad, there is a cement wall partially covered in rocks. If Niko swims against this in the correct spot (the rocks should be just below the waterline) for a few seconds, he will fall onto the seafloor. The player can walk through the cement wall into Blue Hell, although it is very easy to fall into the nearby Booth Tunnel and return to the real world.
 * Near Crockett Avenue and the big rollercoster, there is a Go-Kart racing track. If the player crashes a helicopter with the nose to the ground on the south part of the track, they should sink into Blue Hell. If the player exits the helicopter, they will spawn on whichever street is nearest, or in the water.
 * At the second building by the Leapers Bridge between Albany Ave and Hematite St., go to the front entrance of the building and then jump into the handrail where the mattress is. The player will fall into Blue Hell for 5 seconds and end right back out into Hematite st.
 * In Middle Park West in Jade St., there's an alleyway, which if Niko gets stuck in its entrance (at least with the FIB Buffalo), with a side up and the other on the floor, gets out, and if he then tries to get in again he'll fall into Blue Hell.
 * Sometimes, if The player spawns a vehicle in the subway it will seem to not be there, but if they press F/Y/Triangle, there is a high chance the car will be right under the subway line, causing the player to fall in the car into Blue Hell (tested in PC version).
 * In the dockyard near Francis International Airport, there is an entrance north of the big oil tanks in between the pipe lines and the ground (only works in a helicopter).
 * There is a large fountain-statue located, near the hospital in Easton. Take an Annihilator (it is the easiest to do so), make a little distance to the statue, and ram the Annihilator's nose into the left side of the statue. Tested on PlayStation 3.
 * When driving a car on the airport runway, sometimes when directly hit by the landing gear of a moving plane, a player can be pushed through the ground into Blue Hell. After falling for several seconds the player will respawn on the runway surface. (PS3 tested)
 * Using an Annihilator, fly to the go-kart track at the Funland carnival in Firefly Island. Face towards the ocean and on the top left of the track, the Annihilator can go through the track and into Blue Hell.

The Lost and Damned

 * In the mission Buyer's Market, whilst getting to the ground floor, if the player aims an explosive correctly, they can launch themself out of the building into Blue Hell.

The Ballad of Gay Tony

 * In the mission Boulevard Baby, after the shootout in the Bahama Mamas club, Luis can fall through Blue Hell when walking up the stairs after the shootout, then respawn outside of the club.

Original version

 * It is possible to enter Blue Hell by falling from a great height and landing in the water running through the Los Santos River. This should work even in the especially shallow parts as well. Tested on PS3, using game version 1.01.
 * Jumping onto a Train's car and then accidentally falling in between two cars while the train is in motion can sometimes cause the player to get popped into Blue Hell for a few seconds.
 * It is possible to fall into the Blue Hell by putting a character on Bell's End on Mount Chiliad (confirmed on PS3 with Trevor). From then, switch to any other character, then switch back to whoever is standing on Mount Chiliad.
 * If the player finds a way to bypass the ocean's depth limit and the player swims to the deepest part of the ocean, he will enter a large black abyss. Continuing to swim downwards will result in the player falling through Blue Hell, and then respawning somewhere in San Andreas.
 * In GTA Online, if there are connection problems, or if the server is overloaded, the player may get popped into Blue Hell unexpectedly, and then re-appear back on land a few seconds later.
 * Physical wall breaches ("under the map" locations)
 * At the multi-story car park in Little Seoul, a portion of the left ramp's left side on the ground floor is not solid. The player can walk through the wall here and into Blue Hell.
 * It is possible to access the Blue Hell at the Paleto Bay Sheriff's Office. At the main entrance, it is possible to walk through the windows immediately to the right/left of the doors and fall into the Blue Hell.
 * If glitching inside the IAA Building, it is possible to find invisible walls that, when walked through, will make the player fall into the Blue Hell. It is however possible to die by hitting an invisible solid surface.
 * In the alleyway next to the Bob Mulét, there is a small area with a door. Jumping at a certain point over the door, will climb the wall and be able to walk into the Blue Hell or jump onto a section of solid floor to the right.
 * Next to the bridge in La Mesa, there is a dumpster; push it nearer the wall with a vehicle and climb it in the right place will be an entrance to Blue Hell.
 * In Little Seoul, there is a strip mall across the street from a movie theater. One of the shops has a blue and green sign. The player can enter a completely unsolid building by jumping up and into the wall.
 * On top of the Cluckin' Bell slaughter house in Paleto Bay, there is a small gap in between the roof of the building.
 * If the player is driving a Seashark next to the walls in the Port, near the Merryweather Security Freighter, and gets out of it while still driving, it's very likely they will go through the wall and land on some water, which can send them to Blue Hell by simply diving to the bottom.

Enhanced Version
Many of the wall breach and under-the-map holes present in the original version seem to have been patched in the enhanced version and players can no longer gain access to Blue Hell through those common locations.
 * If the player does not have the lobby to the FIB Headquarters loaded in, they can fall into Blue Hell by glitching into the building through the roof and descending down the elevator shaft. Once they reach the bottom, the player will find themselves in the unmodeled interior of the lobby. Some parts of the floor are not solid and can cause the player to fall through them, before eventually respawning in the street.
 * The player can fall into Blue Hell by ragdolling through a non-solid wall at the top of the IAA Headquarters. This glitch was patched in GTA Online.