The sacred flame here has burned continuously for 1,200 years since Kūkai lit it in the 9th century. It was used to light the Flame of Peace at Hiroshima Peace Memorial Park.

Water boiled in the large tea kettle over the eternal flame appears brownish like tea, but the color comes from dissolved iron in the kettle, not tea leaves.

Couples visit to pledge eternal love like the unquenchable fire, and you can light candles from the 1,200-year-old flame to make wishes.

The hall has been destroyed by fire twice in recent decades (2005 and 2026), but monks managed to rescue and preserve the eternal flame both times.