King Mahasen's Palace, Sri Lanka

King Mahasen's palace was built in the third century but all that remains now are a few standing pillars and the semi-circular doorstep traditionally called Sanda Kada Pahana or Moonstone. The stone doorstep is intricately carved with semi-circular rows of swans and elephants.

https://www.lakpura.com/pages/moonstone-at-mahasen-maligaya?utm_medium=web&utm_campaign=youtube.com&utm_source=lky7m9458v