Maradnias

was a planet.

The Sixth Doctor unintentionally exarcerbated a civil war, resulting in a minor conflict escalating to a level that caused the death of billions. After helping restore the Lux Aeterna, Sadok and Lillith altered events so the Doctor's visit there never happened, undoing both the war he had provoked and the minor conflict he had originally intended to stop. (PROSE: The Quantum Archangel)

In the 108th century, the capital of the Union was on Maradnias. (PROSE: The Crystal Bucephalus)