You may be looking for the space-time network.

A labyrinth was a type of maze.

The Power Complex on Skonnos was a building-sized labyrinth of circuitry designed to generate a pocket black hole to Crinoth. Once complete, the Nimons would then migrate en masse to Skonnos using capsules transmatted through the black hole, exhaust its resources, then move on to the next planet, continuing the Great Journey of Life. (TV: The Horns of Nimon)

The Weevils of Ourouborous Vl, who inhabited the Labyrinth of Death, tried to kill the Fifth Doctor and his companion. (GAME: The First Adventure)

The labyrinth on Serenity was a temporal amplification circuit. It used energy from the tomb of Malador to power the living computer Prophecy and generate the field of goodness around the planet. (AUDIO: The Guardians of Prophecy)

When Gregor Van Baalen took a piece of the TARDIS' architectural reconfiguration system, it created several space loops using the corridors, keeping him, Tricky Van Baalen, and the Eleventh Doctor trapped in a labyrinth. (TV: Journey to the Centre of the TARDIS)

There was a labyrinth under Buda Castle in Budapest. Vlad the Impaler was once imprisoned there. In 1942, it was being used as a military hospital. (AUDIO: The Labyrinth of Buda Castle)

A space-time network called the labyrinth was engineered or made habitable by the Eremites during and following the First Diaspora; it would later be used by various groups for communication and travel during the War in Heaven. (PROSE: The Book of the War)