The Indian Ocean was an Earth ocean bordering Africa, Asia and Australia.
It contained several island nations including Seychelles and Mauritius.
On 25 December 1814, the Seventh Doctor and Chris Cwej became stranded on a small island in the Indian Ocean. (PROSE: No Room)
On 4 June 1926, the cargo ship SS Bernice vanished in the Indian Ocean. (TV: Carnival of Monsters)
Some time in the 1940s, there was a bio-warfare scandal on a remote island in the Indian Ocean. (AUDIO: Mirror, Signal, Manoeuvre)
An Amaranian Star-hopper was fished out of the Indian Ocean by MI6. (COMIC: Hunters of the Burning Stone)