Cliff (The Power of the Doctor)

The Thirteenth Doctor regenerated into the Fourteenth Doctor on a cliff.

History
Choosing to regenerate on a cliff overlooking the sea, so that she could "take in one last sunrise", the Thirteenth Doctor regenerated into the Fourteenth Doctor, who expressed disbelief at his appearance being similar to a previous incarnation. (TV: )

Seemingly getting over the initial shock, the Fourteenth Doctor returned to the TARDIS and left shortly after, (COMIC: ) writing about the "beautiful" experience in a letter to the readers of an annual. (PROSE: )

Behind the scenes

 * The script release specifies the location as in Dorset, although this assertion is not present in any currently released source, valid or otherwise.
 * The usage of the location caused controversy between the landmark owners,, and the BBC following the episode's broadcast, with the Estate calling the BBC "duplicitous and dishonest" about what exactly they were using it for.
 * Despite the controversy, in fact no filming took place at Durdle Door. "Behind the Scenes"-videos show filming taking place on a green screen and a VFX Breakdown by Ben Pickles (AKA "John Smith VFX") shows that the cliff was represented by a 3D Model, slightly modified to allow for the TARDIS to stand on a flat surface.