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JLA Watchtower
JLA Watchtower

Owner: Justice League of America
Designation: Headquarters
Affiliation: Justice League of America
First Appearance:
JLA #4 (April 1997)

Following the disbandment of the various Justice League splinter groups at the request of the United Nations, and the formation of one official Justice League of America, a new perimeter fortress was built on the moon following the Hyperclan invasion in the Sea of Serenity’s Mare Serenitatis crater, between the Ritter and Sabine craters, to accommodate the new team where they monitor the Earth and surrounding universe.

Built by Superman, designed by Green Lantern (John Stewart), and created using technologies from around the universe, the Watchtower is equipped with the most advanced monitoring and transportation systems in the galaxy as well as biospheres for each of its members and prison cells designed to contain the most destructive intergalactic criminals, as well as a Monitor Womb that records every transmission broadcast on Earth, the Watchtower is accessible from Earth by Thanagarian teleportation technology.

Rooms in the tower include:

  • Hydroponic Forest: Here sunlight gathered by the solar tower is converted into oxygen by a process of accelerated photosynthesis using alien plant species from low visibility environments.
  • Transconscious Articulator: A martian machine that scanned an individual's mind and let them live through life scenarios to see how they would play out. Superman uses the machine as a form of therapy when he has anxiety over an action he has taken or about to take. Wonder Woman also used the machine to discover what may happen should she and Batman pursue a relationship.
  • Hall of Heroes: The meeting room of the JLA where the group officially convenes.


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After accusations of elitism had been levelled at the JLA, the group held a recruitment drive for 5 new recruits to make a permnant roster of 12 core members. This first drive resulted in the temporary membership of the Tomorrow Woman before her death. Following an attack by the Key, Green Arrow (Conner Hawk) became their first new member before Wonder Woman was killed during a confrontation with Neron. As Aztek joined the team, Batman recruited Plastic Man to aid in their battle against the Injustice Gang, however, both Green Arrow and Aztek left the team shortly after due to feelings of being inept. A new team was publicly revealed with members of the press allowed access into the Watchtower via STAR Labs teleporters. The new team, consisting of Flash (Wally West), Steel, Huntress, Superman, Aquaman, Plastic Man, Zauriel, and Wonder Woman (Hippolyta), was tested when Prometheus made his public debute by invading the Watchtower.

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Some time later, Lex Luthor, Queen Zazzala, Prometheus and General Eiling enter the Watchtower from the White martian mother ship, which Prometheus had discovered while residing in the Still Zone, as the tower was being assailed by New God troopers. Planting explosives around the tower they destroyed the tower as Mageddon was revealed to be controlling Luthor. While the members went their seperate ways to fight Mageddon, Zauriel stayed in the tower as it was destroyed in order to return to heaven and petition their help in stopping Mageddon.

Following Mageddon's defeat, the tower was slowly reconstructed as Ra's al ghul unleashed the Tower of Babel and the Queen of Fables attacked New York city. During an incident when the dual identities of the JLA split from the heroic personas, Superman had enough spare time to devote 19 hours straight upgrading the tower; creating new wings and redesigning the primary complex.

While serving as an effective headquarters through the reawakening of the White Martians and the awakening of Fernus; the Burning Martian, the Watchtower was destroyed by Superboy Prime during the Infinite Crisis in a bid to cause chaos amongst the Earth’s heroes and to cripple their effectiveness.
While the JLA would reassemble one year later, the ruins of the watchtower were left undisturbed as the team built a new satellite headquarters in orbit around the planet.


  • Following the first tower's destruction, the second "remodeled" Watchtower first appeared in JLA #52 (May, 2001).
  • The Watchtower was built within sight of the moon landing site.
  • The original structure was constructed out of promethium and metals mined from the original satellite.
  • Steel (Henry Irons) has full control of the Watchtower's security systems from his workshop.
  • The tower's Monitor Womb was adapted from the White Martian technology of Z'onn Z'orr. The tower is also equipped with Martian jump ships acquired from the Hyperclan's invasion forces.
  • Sometimes the JLA uses "The Playground" to train or test their powers; the Playground is an uninhabited, oxygenated Jupiter moon, accessible only via JLA Teleporter.
  • The table that the JLA meet at, named the Hall of Heroes, has seats for seven charter members, four additional members, and one "Floating Chair" for specialists who the JLA might require for specific missions.
  • The Watchtower used highly advanced Martian, Thanagarian, Kryptonian, and Earth technology. The arrival of Orion and Big Barda added the technology of New Genesis and Apokolips to the systems as well.
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