Yashima Castle (屋嶋城)
The Yashima-no-ki castle or Yashima castle is an ancient mountain castle once existed in Yashima, the Sanuki Province (present Yashima, Takamatsu City, Kagawa Prefecture).
Summary
It was built in an ancient time, and it is recorded in Nihonshoki (Chronicles of Japan) that Emperor Tenchi built a castle in 667 to prepare an invasion by Tang's forces.
Even today, remains of a gate of the castle (in the southern peak area), stone mounds (on the west slope of the northern peak), and remains of a water reservoir still exist there. In addition, Yashima-dera Temple, said having been built by Ganjin (Jianzhen) in the eighth century, is located in the southern peak area.
The board of education in Takamatsu City excavated remains of the castle gate in 2001, making it clear that the castle once existed actually.