Second Watchtower
Following the gathering of the new team as seen in Justice League of America (vol.2) # 7 (April 2007), a new satellite is presented as headquarters.
The new satellite is an orbiting Watchtower working together with The Hall, a building located in Washington D.C. paid for by Batman and designed by Wonder Woman and John Stewart. Inside the Hall is an archway-type teleportation system, dubbed 'Slideways' in which a person merely need to walk through the archway to be transported to the League's new orbiting satellite headquarter 22,300 miles above Earth.
Jim Lee was called to design the new headquarters. Writer Brad Meltzer: "On the satellite, he did six different designs; some that resembled the old League satellite, resembled the JLU satellite. We kind of took a little from Column A and B. I saw in one of his other designs, he also had these drones and I loved those, and I said, 'Can we put those on there as well? I really want to take that!'"
The satellite has a Danger Room-like training room nicknamed The Kitchen because "if you can't stand the heat...". Meltzer also explains that, for the first time, the satellite has defensive and offensive weaponry. Despite the defense systems, the Watchtower was damaged by the Sinestro Corps. In addition to this, the satellite's teleportation system was hacked into by Hardware after he infiltrated the Hall of Justice disguised as a tourist.
Read more about this topic: Justice League Watchtower