Location from pokemon-unova by
Unova's oldest structure — a spiraled stone tower outside Icirrus where Reshiram or Zekrom sleeps as the Light or Dark Stone.
Dragonspiral is the axis of the Unova mythology. It's where the original Tao dragon split, where Reshiram and Zekrom sleep, and where the Hero sequence that wakes them must take place. Professor Cedric Juniper has published extensively on the interior frescoes. The building's pure age makes it geomantically important — every major Unova legendary myth references it at some point.
A black stone tower spiraling upward seven floors, each accessible via a winding interior staircase. Wind howls through arrow-slit windows. The top floor is open to the sky and holds a central pedestal where the Light or Dark Stone rests. Lightning and fire weather is unnaturally common around the structure.