This is a mound made up of shells thrown away by the people who lived here in the Samhan period(3rd-4th century B.C). It seemed to exist around the first half of the third or fourth century. It was originally a mound of shells on a wide hill at Nangmin-dong and Suan-dong. Most of them were broken down and now only hilly districts of 220 p'yeong is preserved
While a railroad was being constructed in 1930, four earthenware coffins were discovered. It was excavated three times by the National Museum of Korea between 1967 and 1969. It was further excavated partly by the Busan Museum in 1992.
Artifacts which told life in those days were found. For example, earthenware steamers, implements made of animal bone, bones of deer, bulls and horses, irons such as iron ax, burned clods, mixed grass leaves, charcoal, and shellfish such as hard-shelled mussels, oysters and clams, and small amount of stoneware discovered. When the National Museum excavated. ironworks were discovered at the highest elevations in Dongnae.
This is the only shell mound of Samhan period which is designated and preserved in the Busan area. The Dongnae site evidence of the earliest know iron production in Korea. Many well-preserved artifacts were found. The mound was formed at a turning point, when large groups appeared in Dongnae and its districts.