The Sazaedo was built in Aizuwakamatsu city, Fukushima prefecture, during the Edo period. It is a one-way double helix where you go up a spiral slope, and if you keep going straight you will find yourself descending before you know it. The Thirty-Three Kannon statues of the Western Provinces were once enshrined here, making it an entertaining building where you could make a pilgrimage to the Kannon temple just here.It is the only "wooden double helix structure" in the world.