is the secret headquarters of fictional DC Comics' superhero Batman, (the dual identity of millionaire playboy Bruce Wayne), consisting of a series of subterranean caves beneath his residence, Wayne Manor.
Discovered and used long before by Wayne's ancestors as a storehouse as well as a means of transporting escaped slaves during the Civil War era, Wayne himself rediscovered them when he fell through a dilapidated well on his estate.
Upon his initial foray into crime-fighting, Wayne used the caves as a sanctum and to store his then-minimal equipment. As time went on, Wayne found the place ideal to create a stronghold for his war against crime, and has incorporated a plethora of equipment as well as expanding the cave for specific uses.
Often, Bruce Wayne is depicted as having discovered the cave as a child, falling into it during youthful exploration of the grounds. This was shown in the movie Batman Begins as a young Bruce Wayne fell through wood that was covering an abandoned water well.
The cave is accessible in several ways. It can be reached through a secret door in Wayne Manor itself, which is almost always depicted as in the main study, often behind a grandfather clock which unlocks the secret door when the hands are set to the time that Bruce Wayne's parents were murdered, 10:47. Alternately, the study entrance has been shown to be behind a bookcase which slides to the side when a secret button is pushed, revealing the "Bat-Poles", which allow Bruce Wayne and his ward to change into their Batman and Robin costumes en route as they slide down to the cave.
Another secret entrance, covered by a hologram or a camouflaged door, allows access to a service road for the Batmobile. Another alternate enterance is a dry well, highlighted especially during the Knightfall storyline. At one point, Tim Drake and Dick Grayson use the dry well to get into the cave, which they had been locked out of by Jean Paul Valley during his time as Batman.
The Batcave serves as Batman's command center, where he monitors all crisis points in Gotham and the world.
The cave's centerpiece is a supercomputer whose specs are on par with any of those used by leading national security agencies; it permits global surveillance and also connects to a massive information network as well as storing vast amounts of information, both on Batman's foes and his allies. A series of satellite link-ups allows easy access to Batman's information network anywhere in the globe. The systems are protected against unauthorized access, and any attempt to breach this security immediately sends an alert to Batman or Barbara Gordon. Despite the power of Batman's computers, the Justice League Watchtower is known to have more powerful computers (composed of Kyptonian, Thanagarian and Martian technology), and Batman does occasionally use them if he feels his computers are not up to the task.
Additionally, the cave contains state of the art facilities such as: crime lab, various specialized laboratories, mechanized workshops, personal gymnasium, a vast library, parking, docking and hangar space (as appropriate) for his various vehicles as well as separate exits for the various types, trophies of past cases, a large bat colony, and a Justice League teleporter. It also has medical facilities as well as various areas used in training exercises for Batman and his allies.
The cave houses Batman's vast array of specialized vehicles, foremost being the famous Batmobile in all its incarnations (mostly for nostalgia as well as for contingencies, as all are serviceable and in excellent working condition). The 1990s animated series gave rise to the idea that Batman keeps a fleet of regular cars of various models and utility vehicles such as an ambulance as well when the Batmobile would be too conspicuous for a mission. Other vehicles within the complex include various motorcycles, and various air and watercraft such as The Bat-Wing, a single occupant supersonic jet. Another vehicle found in the Batcave is the subway rocket, debuted in Detective Comics #667, during the time when Jean Paul Valley was substituting for Bruce Wayne after Bane broke his back. It let Batman get into Gotham very fast, and could electronically clear a path via Gotham Rail.
The cave is sometimes powered by a nuclear reactor, but most often by a hydro-electric generator made possible by an underground river.
Later comics, specifically the Cataclysm storyline, suggest that Batman has incorporated safeguards against earthquakes and even a potential nuclear catastrophe, outfitting the cave as a virtual bomb shelter or an enhanced Panic Room.
Three memorabilia items often seen in the cave are a defunct full-size mechanical Tyrannosaurus Rex, and an equally large U.S. penny and a Joker playing card. The origins of these trophies are explained in Batman #256: the T. rex comes from an adventure on "Dinosaur Island"; the penny is a trophy from Batman's encounter with a penny-obsessed villain named The Penny Plunderer (in World's Finest Comics #30, 1947). Other "keepsakes" in the cave include Two-Face's original coin, Deathstroke's sword, the shroud of the Vampiric Monk, and over-sized ten-pins.
In the Batman: The Animated Series episode "Almost Got 'Im", the coin was used by Two-Face in an attempt to either crush Batman or kill him from the impact, whichever side the giant coin landed on. Batman managed to free himself from the coin by slicing open the ropes with Two-Face's deciding coins. While telling the story of this to other Batman villains, Two-Face commented that Batman got to keep the giant coin.
There is also a glass case display of Jason Todd's Robin costume as a memorial to him, with the epitaph "A Good Soldier". Barbara Gordon's Batgirl costume also remains on display.
When he lived in the penthouse of the Wayne Foundation building, Batman had a secret basement there equipped as a Batcave as well. In addition, the No Man's Land storyline established that Batman has numerous emergency Batcaves throughout Gotham City in the event that he needs a place to hide and/or resupply. One such Batcave was given to Batgirl Cassandra Cain, during a point where her identity was compromised and she could not walk around without a mask.
During the 1940s through the 1960s, Oliver Queen, the archer known as Green Arrow actually mirrored some of Batman's equipment, having an Arrowplane, Arrowcar, and an Arrowcave. After losing his fortune in the early 70's (prior to the Green Arrow/Green Lantern series), he dropped most of these gimmicks, and they were gone completely by the time he moved to the Seattle post-Crisis. Queen developed an "Arrowcave" of sorts starting with Green Arrow vol. 3 issue 2, in his home. This was destroyed by Dr. Light in Green Arrow #58. The original Arrowcave still exists, and is the last-known location of the monster Solomon Grundy. When Queen mentioned the Arrowcave to Batman he responded "Good lord man, didn't you ever have an original idea back then?"