Nocturne was one of the Doctor's favourite planets in the universe. It was located three parsecs from Earth and "smack in the middle" between the systems of Tau Ceti and Zeta Reticuli.
Glasst City was a major population centre on the planet, with canals and great granite mausoleum-like buildings.
Nocturne was a stopping-off point for those resting or fallen in humanity's war with the Foucoo.
The Fifth Doctor once visited Nocturne in the company of Tegan Jovanka, which he later described as a "particularly lively visit."
The Seventh Doctor later visited Nocturne on at least two occasions, the first time in the company of Melanie Bush and the second in the company of Ace and Hex. (AUDIO: Nocturne)