The main Ieshima Island is blessed with two harbours that are nestled in between two small capes, "Miya" and "Maura" on the east and west. On the western end lies Bozejima where the stones quarried for land reclamation use are mainly transported by the stone cargo ships.
The stones are mainly used for levee protection works, disaster prevention and reduction works, airport construction, construction of man-made islands planned in the Osaka Bay Phoenix Project and reefs etc.
At its peak, the industry produced a record 13 million cubic meters of stones a year for reclamation use, the highest in Japan for a single region.
Currently, it supplies stones to not only the Osaka region but construction sites all around the country as well.

4-point pitching technique to support accuracy

As marine operations fluctuate widely depending on the climate and sea condition, accurate technology is required.
Since the environment is different from that on land, the work is carried out with the ship fixed in location.
However, as the shapes of the stones are not uniform and the loading points are also not even, following the blueprint for the construction is an important process which requires a high level of technical skills honed by years of experience.