Mount Koya is the center of Shingon Buddhism, an important Buddhist sect which was introduced to Japan in 805 by Kobo Daishi. Since then over one hundred temples have sprung up along the streets of Koyasan. The most important among them are Kongobuji, the head temple of Shingon Buddhism, and Okunoin, the site of Kobo Daishi’s mausoleum. Koya-san and its surrounds is a UNESCO World Heritage Site.