Waypoint

Space-time Waypoints were points in time and space that became supercharged with vortex energy.

During a temporal crisis which grounded TARDISes and similar machines throughout the universe, the Doctors realised they could only travel from one Waypoint to the next, draining each of vortex energy to temporarily, messily re-power their TARDIS before depleting their reserves with the next hop. (GAME: Lost in Time)

These Waypoints included:
 * The UNIT Lab, which became charged with vortex energy due to "almost passing through the event horizon of a black hole" (GAME: Lost in Time) when Omega transported it to his anti-matter universe. (TV: The Three Doctors)
 * Atlantis, (TV: The Time Monster) which has been frozen in its final moments in a time eddy) because of the Crystal of Kronos. (GAME: Lost in Time)
 * The Dalek City on Skaro at an early point in its history (TV: The Daleks) that future Daleks had visited. (GAME: Lost in Time)
 * The Panopticon on Gallifrey (TV: The Deadly Assassin)
 * The desert-road site in Nevada where Clara Oswald parted ways with the Twelfth Doctor (TV: Hell Bent)
 * The Underhenge right before the Eleventh Doctor was placed in the Pandorica. (TV: The Pandorica Opens)
 * The Minyan spaceship, R1C. (TV: Underworld)
 * Victorian London during the dinosaur attack. (TV: Deep Breath)
 * Mars during the British Army drilling skirmish. (TV: Empress of Mars)
 * The Moonbase Laika occupied by UNIT on the Moon. (TV: The Moonbase)