Kamaishi Mine (in Kamaishi City, Iwate Prefecture) is a former mine for iron ore and copper ore. In service for some 150 years, its tunnels stretch for more than 1,000 kilometers altogether. Like a gigantic ant farm, the tunnels extend outward at many heights, ranging from 150 to 980 meters above sea level, across an area that measures 8 kilometers north to south by 4 kilometers east to west. Only a part of this valuable underground space is currently in use by businesses and research institutions for various purposes.

We are now inviting ideas for use of the Karematsuzawa Zuido tunnel, which stretches for more than 5 straight kilometers along a north-south axis. The tunnel was closed in 1993, when large-scale mining was discontinued, but we seek now to give it a new purpose.