Moon-stone also known as, Sandakada pahana, is a unique feature of the Sinhalese architecture of ancient Sri Lanka. It is an elaborately carved semi-circular stone slab, usually placed at the bottom of staircases and entrances. First seen in the latter stage of the Anuradhapura period, the sandakada pahana evolved through the periods of other Sri Lankan kingdoms. According to historians, the sandakada pahana symbolises the cycle of Saṃsāra in Buddhism.