noun
Nagaoka-kyō (historical capital of Japan, 784–794)
Historical term referring to the short-lived capital established by Emperor Kanmu before the move to Heian-kyō (Kyoto).
長岡京は、784年から794年までの日本の首都でした。
Nagaoka-kyō was the capital of Japan from 784 to 794.
noun
Nagaokakyō (city in Kyoto Prefecture)
Only with reading ながおかきょう
Modern city name; the reading is ながおかきょう. The historical capital reading ながおかのみやこ is not used for the city.
長岡京市は京都府の南部に位置しています。
Nagaokakyō City is located in the southern part of Kyoto Prefecture.