Tadao Ando's involvement with Naoshima Island dates back to the late 1980s, when he first designed a museum for contemporary art, conceived as a series of typically ascetic containers partially submerged underground so as to impinge as lightly as possible on the landscape. Though there is an industrial and commercial zone on the northern part of the island, its southern tip is given over to the Seto Inland Sea National Park. This latest building, the Chichu Art Museum, extends the notion of subterranean excavation even further; here the entire volume is set underground to preserve the surrounding salt pans. Even though Ando is well known for his formal and material reticence, this sets new standards. The building literally becomes part of the topography, registering as a series of sunken courtyards set in a lush green hill overlooking the sea. Bunkered down in the landscape, the starkness and introversion of the concrete courtyards do little to suggest the presence of an art museum; rather they call to mind the brooding archaeological relics of military defence or a long lost civilisation.