Introduction to the burnt wood stove: The burnt wood stove is located in the southeast of the outer circle of the Circular Mound Altar. It is located in the south and faces north. It is cylindrical and made of green glazed bricks. There are nine steps on the east, west and south sides. The burnt wood stove is used to burn offerings to the emperor (God of Heaven) during the Winter Solstice Heaven Sacrifice Ceremony.