The Kitazawa Flotation Plant on Sado Island of Niigata Prefecture is the site of a facility that was formerly used for ore processing and sorting, removing the unused minerals from mined ore. This facility was constructed in the late 1930s via large-scale capital investment from wartimes. While in operation, it could process over 50,000 tons of ore in just one month, leading it to be called the greatest flotation plant in the East. However, just under 20 years after the start of operations, the facility was abandoned, and grass and moss started to grow in the ruins of the giant buildings. Coupled with the style of the buildings, the sight of the ruins looks just as if it were taken from a scene from the Studio Ghibli film Laputa: Castle in the Sky. In order to increase public knowledge of the of the site as a historical landmark that supported Showa-era mine modernization, illuminations and projection mapping events that coincide with the tourist season are now held, and it is garnering attention as a new sightseeing spot.