The Altean Colony was constructed on a planet in the Quantum Abyss by Prince Lotor. He had constructed this colony to restore Altea, Alteans, and Altean culture. Lotor hid the colony in the Abyss so the Galra Empire won't find it. He helped construct homes, farms and other essential facilities. The refugees saw Lotor as a God or savior. In return Lotor gave them protection. But this wasn't Lotor's true intentions.
Altean Colonization[]
Following his exile from the Galra Empire, Prince Lotor had gathered all the Surviving Alteans who were off-world after Altea had been destroyed and convinced them all to come with him to a hidden planet deep within the quantum abyss where they would be safe from Zarkon’s grasp and created a virtual paradise where Altean culture and society could thrive. It's also likely during this time, Lotor had begun to harness quintessence from Altean life force from the colonists who had met the qualifications for it, killing thousands for generations.
Harvesting Quintessance[]
Romelle, told the Paladins, Shiro, Coran, and Krolia about what Lotor was dong to the Alteans there. Lotor's true intentions were to harvest Quintessence from the Alteans. He lied to them about a second colony. And that going here was of high honor. Many innocent Alteans were taken to this "second colony" only to find out their Quintessance was going to be harvested. Romelle eventually finds out what happens when her brother escapes in a shuttle pod and back to the colony. He tells her it's all a lie and that Lotor was harvesting Quitessance from Alteans. The Paladins eventually stop Lotor and his schemes by killing him in the Quintessance Feild.
Honerva's Army[]
The witch Hagar also known Honerva rose to power after the downfall of the Galran Empire in VLD Season 8. She departed to the Abyss and found the Colony her son, Lotor, had established. Wanting revenge for the death of her son, she recruited the Alteans at the colony. She told them Voltron had killed Lotor. Doing so made the Alteans want revenge as well, so the Alteans constructed Robeasts that almost resembled the Sincline Mech Lotor controlled. Together they tried to destroy Voltron and the Coalition.
After the final battle[]
After the final battle in the realm that contained all the realities, the Alteans returned to the new Altea. They and Coran began to reconstruct everything that was on the original Altea. An example of addition to the new Altea was the statue of Princess Allura.