Later, the name of the Site was changed to "Heijo-kyu seki" (平城宮跡) since the character "址" ('shi' or 'ato') in "Heijo-kyu shi" (平城宮址) was out of kanji for common use (a list of 1945 kanji established in 1981).
のちに址（し・あと）が常用漢字外であるため平城宮跡（へいじょうきゅうせき）と書かれるようになる。