Sonohyan-utaki is a sacred grove of trees and plants of the traditional indigenous Ryukyuan religion. It is located on the grounds of Shuri Castle in Naha, Okinawa, a few paces away from the Shureimon castle gate. The utaki, or more specifically its stone gate, is one of a number of sites which together comprise the UNESCO World Heritage Site officially described as Gusuku Sites and Related Properties of the Kingdom of Ryukyu, and has been designated an Important Cultural Property by the Japanese national government.
While the gates were once opened only for the king, today they are always closed, and so the gates have in a way become a sacred space themselves, representative of the actual sacred space behind them. Many travellers and locals come to pray at the gates.
Wikipedia https://en.wikipedia.org/wiki/Sonohyan-utaki
Address Urazoe, Japan
Coordinates 26°13'5.148" N 127°43'2.372" E