2022.10.01-10.03 Shunichi Ikeda + Genki Watanabe Koyasan (Wakayama Prefecture), a sacred site of Japanese Buddhism with a history of 1,200 years, was inscribed on the UNESCO World Heritage List in 2004 and again in 2016, and is one of the world’s most renowned religious cities. It is also a popular tourist destination, attracting many international visitors prior to the COVID-19 pandemic. Through the distinctive light environment created by the numerous temples and shrines, as well as through the experience of staying at temple lodgings (shukubō), we conducted an investigation into this extraordinary lighting culture from the perspective of the Lighting Detectives. Koyasan is a town situated in a mountain basin at an altitude of 800 meters, surrounded by peaks of around 1,000 meters in northern Wakayama Prefecture. It was founded about 1,200 years ago, in the early Heian period, by the Buddhist monk Kōbō Daishi (Kūkai) as a sacred site of Japanese Buddhism, with Danjō Garan serving as the central temple complex of this religious city.Originally, the entire area of Koyasan was considered part of the grounds of Kongōbu-ji Temple.For us, this was the first time to focus on a religious city in an urban lighting survey. We wanted to examine what the nightscape of this temple town looks like and how the lighting culture of Japan and Buddhism manifests itself in various aspects. ■Okunoin, Kongōbu-ji, Head Temple of Koyasan Shingon Buddhism Okunoin is an expansive cemetery stretching about 2…