Tomb from the late Yayoi period, where it is said that the evil horse kingdom existed about 4 years ago. Lid of a stone weighing more than 10 kilograms is slowly lifted using heavy machinery.
Three of the four lids were lifted, but all of them were buried with earth and sand. Traces of the use of red pigment were found inside the tomb. A bronze sword has also been unearthed as a grave item. Yoshinogari Ruins is the largest Yayoa period settlement site in Japan.