Komoritsuka Burial Mound

Located just east of Bitchu Kokubun-ji Temple, this 100m total length keyhole-shaped burial mound contains the 4th largest horizontal stone chamber in Japan.
It is said that this is the tomb of 'Kurohime', known for the legend of her romance with Emperor Nintoku, the 16th emperor of Japan, which is why the mound is also sometimes referred to as the 'Kurohime Burial Mound'.
However, recent research has determined a gap between the time of its construction and the time that Kurohime was alive, leading to to theories that this is actually the resting place of someone else entirely.