The Watchtower

The Watchtower is an orbiting satellite, and the true headquarters of the Justice League. League members are transported to the Watchtower from the Hall of Justice and presumably the Cave. The Watchtower has sensors that can detect immense energy surges on the surface of the planet, but no weapons systems.

History
The Justice League convened a meeting to discuss the possibility of admitting additional members to the League.

Background in other media

 * The first JLA base to use the name "Watchtower" was built on the moon's surface during the Grant Morrison run of the JLA series. That base would later be destroyed during the Infinite Crisis. A new orbiting satellite Watchtower would be built following the One Year Later jump.
 * Before the Watchtower, the JLA had another orbiting satellite base simply named "The JLA Satellite".
 * This marks the 6th television use of the Watchtower.
 * In Justice League, Batman designed and built the first Watchtower as an orbiting satellite as the first HQ for the League. It would later be destroyed by Batman during an alien invasion. In the later series Justice League Unlimited, a new and larger Watchtower was built to house a massive influx of new JL members. This base also includes a powerful laser cannon that could cause massive levels of destruction.
 * In The Batman series, the Watchtower is instead designed to look like the Hall of Justice, only built into an orbiting asteroid.
 * In the feature Justice League: Crisis on Two Earths, the Watchtower has only recently been built, and is a much larger and complex design than previous versions.
 * In the live action series Smallville, which depicts Superman's teenage years, the Watchtower is at the top of massive skyscraper in Metropolis. The title of Watchtower is not only the name of the Justice League's headquarters, but also is used as the super-hero codename for Chloe Sullivan (and later Tess Mercer), who acts as their online command & control at the HQ. This is the first Watchtower HQ that is Earth-based.
 * In Batman: The Brave and the Bold, the Watchtower is based on the old satellite, and used by the Justice League and Justice League International.