Insū

What insū means

Insū is the quantity recorded for a designated or registered cultural property. In the National Cultural Properties Database it sits directly under the name and states what the designation contains and how much of it.

The rules governing certificates of designation list the name and quantity of the property as the first item to be entered on the certificate issued to the owner. Where a quantity has sub-items, the breakdown goes on a supplementary sheet attached to the certificate and treated as part of it. The figure is part of the substance of the designation rather than a note appended to it.

Counters vary with the kind of object. Architecture normally uses the counter for buildings, while a waterworks treated as a single installation is counted as one place. Flat objects such as documents and boards take another counter again, which is how the six ridge tablets recorded as Tsuketari at one shrine are expressed. Copying the wording of the record is safer than inferring a counter from the name of the property.

Records for a Registered Tangible Cultural Property carry the same field. The two systems differ, but both state a quantity in the same way.

Cases and structures are different figures

Architectural statistics carry two numbers. As of 1 August 2026 there were 2,605 architectural designations as an Important Cultural Property, covering 5,597 structures, of which 233 designations covering 303 structures held National Treasure rank. The first figure counts designations, the second counts buildings, and they diverge because one designation frequently covers several buildings.

Temple, shrine and castle precincts are the usual reason. Where a group has been designated as one case, the recorded quantity is the figure for the whole group rather than for the principal building alone. A record reading fifteen structures means the designation covers fifteen.

Fine arts behave the same way. A set of vessels or a sequence of documents designated together is recorded as the full number of pieces. Since national statistics and individual records count in different units, it is worth being clear which of the two a given figure comes from.