Watching the Third Doctor's run, and he just casually mentioned being several thousand years old. This was a season after he'd been forced to regenerate and was trapped on Earth. And I know this came long before the modern run where they claimed to be 900 years old...and long before we found out the Doctor is even older than they know because they had their memory erased....so this makes it head cannon, to me, that the missing memories started bleeding through when he was Three.

#DoctorWho