Zakimi Castle, Ryukyu Kingdom

Small urns used for royalty in the mausoleums of Okinawa.

 Right here in Yomitan is Zakimi Castle, a UNESCO World Heritage Site, perched atop a hill overlooking Eastern Okinawa and the East China Sea.
The castle is made of limestone, and was built between 1416 and 1422.

It's a pretty intricate fortress, and they believe it to be one of the first structures in Japan built using huge stones.