Mount Kōya (高野山, Kōya-san) is a large temple settlement in Wakayama Prefecture, Japan to the south of Osaka.

In the strictest sense, Mount Kōya is the mountain name (sangō) of Kongōbu-ji Temple, the ecclesiastical headquarters of the Kōyasan sect of Shingon Buddhism.

[1] First settled in 819 by the monk Kūkai, Mount Kōya is primarily known as the world headquarters of the Kōyasan Shingon sect of Japanese Buddhism.

[7] The complex includes a memorial hall and cemetery honoring Japanese who were imprisoned or executed for committing atrocities during World War II.

Many Buddhist monasteries on the mountain function as hotels for visitors providing traditional accommodation with an evening meal and breakfast.