With over eight-hundred episodes and nearly three-hundred adventures on TV, the Doctor has visited countless strange worlds and unusual time periods... but not all of them have we actually seen on-screen.
Referenced in passing, left to the imagination or entirely off-limits, we've never seen these notable locales in the Doctor Who Universe explored by the Time Lord on our TV screens.
From the home planets of several iconic alien menaces to key locations in the programme the Doctor has never actually stepped foot in - these are the most intriguing and most surprising places we've never seen.
This list will be focusing on the Doctor Who TV series only, so you might find that planets, time periods, and locations travelled to in comics, books, or Big Finish Audio dramas appear on this list. These interesting locations, however, should be seen on our screens - with some even helping to fill in important gaps in the Doctor's timeline.
Some of these entries are surprising, and some of them have been discussed at length, but all of them are important to Doctor Who's history.
Read on to discover the top picks for Places The Doctor Has Never Visited On-Screen...
10. The Zygon Homeworld
Referred to as 'Zygor' in extended media, the home planet of the Zygons has never actually appeared on TV.
Said to have been destroyed in the Time War in 2013's The Day of the Doctor, the shapechanging Zygons have never been depicted occupying their own planet in the show.
In 1975's Terror of the Zygons, the Zygons had fled to Earth in the 12th Century when their planet had been destroyed 'in a recent catastrophe.' In this adventure, they had tried to overpower and occupy the Earth, despite being few in number.
To assist in their conquest, they deployed a Skarasen - a cyborg creature native to their world. The Skarasen, residing in Loch Ness in Scotland, became known as the Loch Ness Monster and had held a legendary, mythical status for centuries.
Defeated by the Fourth Doctor, Sarah Jane Smith and UNIT, the next appearance of the Zygons was The Day of the Doctor where they again, were trying to colonise Earth.
Realising that the 16th Century Earth they had crashed in wasn't technologically advanced for them to dominate, they froze themselves in stasis cubes to be woken in the 21st Century. During this adventure, and 2015's The Zygon Invasion/The Zygon Inversion, the Zygons continued their bid to conquer the Earth - with many displaced Zygons even being allowed to seek refuge across the planet.
We're yet to see the Zygons in their natural habitat, but with 2017's Empress of Mars finally depicting the Ice Warriors on Mars, the Zygons might have a home sooner or later.