From Battlestar Wiki, the free, open content Battlestar Galactica encyclopedia and episode guide
History and Use
This structure was built around the original ship of the Final Five (Islanded in a Stream of Stars podcast). The vessel was used by Samuel Anders, Tory Foster, Ellen Tigh, Saul Tigh, and Galen Tyrol to travel to the Twelve Colonies from the devastated remains of Earth, backtracking the path their ancestors had taken from Kobol and then following the path of the twelve tribes of humanity. At one point, the ship stopped at The Temple of Hopes.
The expanded structure was "home" to the humanoid and Centurion Cylons after the war. The eight numbered humanoid models were presumably developed by Anders, Foster, the Tighs, and Tyrol here. Their original resurrection equipment was still on the Colony (TRS: "No Exit"), as was their original sublight starship.
The Colony fell into the hands of the Number Ones/Cavils after they usurped the Final Five. Prior to the Cylon Civil War, Cavil keeps the Colony secret (TRS: "No Exit"). Cavil moves the Colony shortly before the start of the civil war, indicating that the structure is FTL-capable (TRS: "Islanded in a Stream of Stars"). It is positioned in a stable orbit inside the accretion disc of a naked singularity (TRS: "Daybreak, Part I").
The Colony serves as home base for the Ones, Fours, Fives, and Boomer. Hera Agathon is brought to the Colony for experimentation, to determine what makes her a successful human-Cylon hybrid and replicate it (TRS: "Daybreak, Part I").
There are both original-model Cylon Raiders (mechanical fighter craft which require pilots) and the newer autonomous Raider models inside the Colony, and both 0005 and updated Centurion units. The Colony's systems are controlled by multiple Hybrids (TRS: "Islanded in a Stream of Stars", "Daybreak, Part II"). It is armed with a large array of quadruple point defence gun batteries and missle launchers (TRS: "Daybreak, Part II").
The Colony is destroyed when Margaret Edmonson's corpse inadvertantly launches several nukes at it from her Raptor, causing massive damage and the loss of its stable orbit around the singularity (TRS: "Daybreak, Part II").
The final battle between humans and Cylons, the Battle of The Colony, takes place here when Galactica launches a rescue mission for Hera Agathon. Among the dead in the battle are numerous Centurions, at least three Dorals, three Simons, Cavil, and Boomer, as well as any who are onboard the structure when it falls into the black hole.