Dronid

Dronid's name should be Drornid but there was a typo in a first edition of Bartholomew's Gazeteer so the rest of the universe (except the natives of Dronid) called it Dronid. (EDA: Alien Bodies)

Early History
Some time ago a Gallifreyan Cardinal attempted to set up his own High Council on the planet Dronid. He put together an army with the hopes of overthrowing the Gallifreyan High Council. He was dragged back to Gallifrey leaving a lot of Gallifreyan time technology all over the planet Dronid. (EDA: Alien Bodies)

The War
As the Faction Paradox came to power they settled a base on the planet Dronid.

In the latter days of their war with The Enemy the Time Lords attempted to go back in Time and destroy Dronid, but found that the Enemy had crystallized Dronid into their own version of the Web of Time leaving it untouchable to the Time Lord's weapons.

However, the Time Lords still attacked the planet destroying the surface with a virus. The Doctor in one of his last incarnations was there and died on Dronid. (EDA: Alien Bodies)

Behind the scenes

 * On Dronid's name Lance Parkin notes: "In the note about Drornid it's claimed that I got the name of the planet wrong in A History of the Universe. The spelling 'Drornid' appears in the script which came with the video (of Shada). The spelling 'Dronid' first appeared in The Universal Databank - the joke that Lawrence is making is that so many people read the 'guidebook' without checking the facts that the name 'Dronid' stuck in the end! For the record, it's spelt 'Drornid' in A History of the Universe (p.251)."