National Treasures refer to cultural assets designated by the nation, specifically by the Minister of Education, Culture, Sports, Science and Technology, due to their high value among the tangible cultural properties specified by the Cultural Properties Protection Law.
These include architecture, paintings, sculptures, crafts, writings and books, ancient documents, archaeological materials, and historical materials.
文化庁 国指定文化財等データベース https://kunishitei.bunka.go.jp/bsys/index

WANDAR 国宝一覧 都道府県別 https://wanderkokuho.com/kokuhodb2
Tripadvisor 口コミで選んだ、国宝が見られる人気スポットランキング Top30 https://www.tripadvisor.jp/blog/news/ranking/kokuho-30/