Ryûtan ("dragon depths") is a pond located near Shuri castle, the Ryukyuan royal palace.
It was designed by Chinese-born Ryukyuan official Kaiki during the reign of King Shô Hashi, and collects water from the "zuisen" pure water spring at the palace. When Chinese investiture envoys were resident on the island, they would celebrate Chrysanthemum Festival with boats on the pond, while members of the court performed music and dances.
A hall dedicated to the goddess Benten stands amidst the pond (then called Enkan Pond); it was built in 1502 to house a collection of sutras from Korea. A small bridge, originally called Kanren-bashi and later renamed Tennyo-bashi, was built at the same time and provides access to the hall. The bridge is built of Ryukyuan limestone, in a southern Chinese style. The hall was destroyed in the 1609 invasion of Ryûkyû along with the sutra collection, but the hall was rebuilt by 1621.[1]