Capital planet of the Galactic Empire for roughly twelve thousand years, as told by Isaac Asimov's Foundation series. Destroyed approximately 300 F.E.

With a population of forty billion, all of Trantor's land surface, excepting only the Imperial Grounds, is covered by metal domes. Trantor is essentially a city on a planetary scale with the sole purpose of administering the Galactic Empire.

Twenty agricultural planets support the inhabitants of the mighty planet, and its people have burrowed so deeply into the planet's crust that its main source of energy is geothermal heat.

Trantor is composed of many unique sectors. The Imperial Sector surrounds the Imperial Grounds and is one of the wealthiest sectors on the planet. The Dahl Sector is known for its heat-energy capacity. The Mycogenian Sector is shrouded in secrecy, allows nearly no external contact, and exports the rarest and best food products in the Galaxy.

Trantor is also the center of learning in the Galaxy. It houses the great Galactic Library, as well as many distinguished universities. First among these is Streeling University, where Hari Seldon developed psychohistory.