Communication Hub

The "Communication Hub" was an ancient place that was once used by the Crystal Gems. The place made its first appearance in "Coach Steven", when Sugilite demolished it with her flail.

The Crystal Gems visit it again in "Cry for Help" after discovering a transmission from Peridot, seeing that she has assembled a signal tower out of the pillars.

History
Not much is known about this place, considering its very short existence and history lecture in the episode "Coach Steven." The Communication Hub used to be a place where, at one time, Crystal Gems were able to send messages over long distances. The place contained many huge pillars adorned with triangular patterns.

In "Coach Steven", the Communication Hub had started to emit bursts of electromagnetic radiation, which, stated by Garnet, was hurting television. The Crystal Gems traveled to the hub and destroyed the structure by having Garnet and Amethyst fuse into the gigantic fusion Gem known as Sugilite who proceeded to reduce the place to rubble. Doing so, a chunk of one of the pillars destroyed the Warp Pad located by the site.

In "Cry for Help", the Gems find out that Peridot is using the hub in order to contact Homeworld, specifically Yellow Diamond, causing the TVs on Earth to intercept the message. The group travels there by warping with Lion, since the warp pad is still destroyed. The Gems find a tower crudely assembled out of pillars and slabs salvaged from the ruins. Garnet, afraid that Sugilite will go out of control again, fuses with Pearl to form Sardonyx. Sardonyx carefully destroys certain pillars, allowing the hub to become inactive. The next day, they find the tower reactivated, so Pearl and Garnet form Sardonyx to disable it and stop the transmission. When Steven and Amethyst stake out the hub though, they discover that Pearl was the one reactivating the hubs. When Garnet found this out, Sugilite was formed again, demolishing the tower with a single punch.

Trivia

 * A floating chunk of crystals are seen in the center of the first floor of the hub. Their function or relation to the hub is unknown.
 * The hub was shooting beams of energy into space in a similar fashion to how other Gem temples shot beams of energy into space while being activated or destroyed (such as the Pyramid Temple).
 * The place was, according to the looks of it, abandoned, similarly to how the Lunar Sea Spire was abandoned before Steven accidentally sank the temple into the ocean.
 * This is one of the few places to have its Warp Pad destroyed.
 * It is powerful enough to send a message to Homeworld.
 * This is where Amethyst sung her first solo in "Cry for Help", Tower of Mistakes.
 * It was destroyed by Sugilite in "Coach Steven", but rebuilt by Peridot and Pearl in "Cry for Help" before it was finally again destroyed by Sugilite in the same episode.