Pyramid of the Rings of Akhaten

The Pyramid of the Rings of Akhaten was a pyramidic temple for the Old God. Located on an asteroid orbiting Akhaten, the Pyramid was a holy site for the Sun-singers of Akhet. They believed that life in the universe originated there.

The door to the Pyramid was dead-locked, although the Eleventh Doctor managed to lift it with his sonic screwdriver, finding the door "really, quite astonishingly heavy." The door could be also be opened by a 'secret song', which every Queen of Years knew.

It was home to the Mummy, who locals believed was the Old God. The Chorister also resided there, singing the Long Song to keep the Mummy asleep. (TV: The Rings of Akhaten)

History
When, at one Festival of Offerings, the Long Song ended, Merry Galel, the Queen of Years at the time, was taken by force to the Pyramid to be sacrificed. The Chorister teleported out to save his soul from 'Grandfather'.

The Eleventh Doctor and Clara Oswald, who were visiting at the time, travelled there by moped, and saved Merry. (TV: The Rings of Akhaten) פירמידת הטבעות של אקהטן