Space-time tunnel

A space-time tunnel, also known as a hyperspatial tunnel, were used by the Nimon to travel through space, linked by black holes. (TV: The Horns of Nimon)

Behind the scenes

 * In NOTVALID: Scream of the Shalka, the Shalka use a space-time tunnel, also known as a warp gate, to invade Earth from their homeworld.