This is not a museum in any conventional sense. It's a large concrete shell open to the sky, where cut-outs frame snapshots of blue clouds and green hills. The 'art' is the building itself and the water that pools mysteriously on its floor, forming and dissolving in patterns governed by invisible forces. You remove your shoes, sit on the cool concrete, and simply observe the interplay of water, light, and silence. It's one of the most meditative spaces in Japan, and visitors often find themselves sitting here far longer than planned.