Heavenly Heart Stone, or Round Heart Stone, is located at the center of the upper terrace of the Circular Mound.If one speaks standing on it, he could hear strong echoes.

• 天心石,又叫圆心石,位于圜丘台上层台面中心。人站在圜丘台上说话,会听到从地层深处传来的明亮而深沉的回响。