Medusa Cascade

The Medusa Cascade, a location where there was a time rift, was first visited by the Doctor when he was 90. (DW:The Stolen Earth) At some point, the Doctor closed the rift in time and space. (DW: Last of the Time Lords)


 * Based on the Master's familiarity with the event, he was most likely involved, possibly opening the time rift himself.

Evelina, who could see the future, mentions the Medusa Cascade when commenting on The Doctor saying "Your real name is hidden. It burns in the stars, in the Cascade of Medusa herself". (DW: The Fires of Pompeii)

The Doctor told Donna Noble that, amongst other places, he wanted to take her to visit the Fifteenth Broken Moon of the Medusa Cascade. (DW: The Sontaran Stratagem)

The Doctor used the words "Medusa Cascade" to see if the possessed Sky Silvestry would repeat him. (DW: Midnight)

The Medusa Cascade was also the place where Davros's New Dalek Empire moved 27 planets to form a sort of interplanetary device. The planets could not be normally found as they were out of sync from the rest of the universe by about a second. (DW: The Stolen Earth). He placed them there so that when his Reality Bomb was set off it could penetrate the space-time rift in the Cascade and spread the bomb's destructive force across every universe and all of existence.

This led to the War in the Medusa Cascade. It ended with the destruction of the Daleks by the Doctor, his clone and all of his companions and also the return of all of the planets to their correct locations in space. The Cascade was also used to send Jackie Tyler, Rose Tyler and the Doctor's clone to Pete's World.