large scale use of building stones , techniques used to place huge stone blocks on top of each other and processing hard stone were applied to construct stone foundations , production of a sarcophagus and fuki-ishi (a stone covering an old tomb ) were discovered , and a construction method called hanchiku (hard soil made using wooden frames ) to make a hill tomb was discovered , and a large scale civil engineering such as making ponds , ditches , and embankments were carried out at the time . 石室の造営や石棺の製作と古墳の葺石および居館周濠の貼石などに大量の石材の使用と、大きな石材を積み上げ固い石を加工するといった技術がみられ、墳丘の造成に版築と呼ばれる工法が使用されたり、池溝の開作や築堤など大規模な土木工事が行われるようになっていた。
