Spacerock is a level 5 city, and the capital city of Jetstone. It was formerly the capital of the Spacerock side, under the command of Spacerock the King, and at Spacerock the Battle fell to Jetstone who appropriated it as their new capital.
Unlike most cities, Spacerock does not have Tunnels. Rather, it has "an unusually ornate and well-defended Garrison. Its outer structure is not merely a wall, but a full twelve-story palace complex of rooms and chambers."
Also, instead of having an open Courtyard in its Garrison, Spacerock's Courtyard is covered by "a vaulted roof of smoked glass panels." This area is referred to as the Atrium by Jetstone and covers the entire twelve-story height of the main garrison structure.LIAB Text 25 The area above the atrium is dominated by the Tower of Jenga.LIAB Text 47
Real World References
The name of the faction, Jetstone, seems to be a portmanteau of the names of the Hanna-Barbera cartoons The Jetsons and The Flintstones. The capital, Spacerock, is named according to the themes on the two shows. It might be meant as a portmanteau of something starting with "Space" and Bedrock, the city the Flintstones live in. Space rock is also a subgenre of rock music that emerged in the late 1960s music scene in Britain.
Spacerock is a close match to the movie Spaceballs as many of the objects in the movie were refered to as Spaceballs: The (item) much like the various aspects of Spacerock are refered to as Spacerock the Side, King, City, Battle etc..