The Jinyama burial mounds are famous as a burial mound group consisting of five rectangularshaped graves with burial mound (funkyū bo) built in the last third of the Middle Yayoi period. However beyond that, according to the investigated material pottery unearthed from the tomb group also shows features of the first third of the Late Yayoi period. Furthermore, the tombs were extended and some traces of long-term use were found. Hidden in the northern part of the Bingo region such cases concerning Yayoi period graves (funbo) can also be identified.
In addition, the results of the analysis of carbides – conducted by Paleo-Labo Co., Ltd. who carried out 14C dating using Accelerator Mass Spectrometry (AMS) – gathered from pottery unearthed at the Jinyama group of graves and other sites in the northern part of the Bingo region are presented.