| Location | Habikino / Fujiidera, Osaka |
|---|---|
| Shape | Square mound |
| Mound length | 45 m |
| Period | 5th c. |
| World Heritage | Mozu-Furuichi Kofun Group (UNESCO) |
A square mound (45m long) located west of Karusato Otsuka Kofun (Hakucho/White Bird Mausoleum, 200m). A 5th-century accessory mound of the main tomb. The name "Nishiumaduka" (West Horse Mound) suggests a connection to horse-related grave goods or ancient horse pastures in the area. Not IHA-managed; administered by Habikino City. A constituent monument of the Furuichi group square mound cluster.Constituent monument of the "Mozu-Furuichi Kofun Group" UNESCO WHS (2019). The southern Furuichi group includes Karusato Otsuka Kofun (Hakucho Mausoleum, 200m) and surrounding square mounds including Nishiumaduka and Higashiumaduka, forming a sub-cluster sometimes called the "Karuri kofun group." The name "umaduka" (horse mound) may also allude to ancient state-run horse pastures (maki), reflecting the Kawachi Plain's historical importance as a horse-breeding region. Research and excavation in the Furuichi group continue, with new findings on these square mounds being regularly published.
Excavation records are limited. Surface-collected haniwa and pottery fragments have been reported, but burial chamber details are unconfirmed.