Located slightly north of Sakai City, this group of ancient tombs is said to have once had over 100 mounds, but today, separated by Daisen Park, only 44 remain, including the Nintoku Emperor's Tomb (486m long), the Richu Emperor's Tomb (365m long), the Itasuke Tomb (146m long) to the east, the Gobyoyama Tomb (203m long), the Nisanzai Tomb (290m long), and the Hanzei Emperor's Tomb (148m long) to the north. Many of these are huge keyhole-shaped tombs that are thought to have been built as tombs for great kings between the late 4th century or early 5th century and the late 6th century. According to the Nihon Shoki, the name Mozu came about when the tomb of Emperor Nintoku was being built in this place, which was formerly called Ishizunohara. A deer jumped into the crowd of people working on the construction, collapsed and died, and a bush warbler flew out of the deer's ear, having eaten the inside of the ear. This is how the place was renamed Mozu.