Mount Kōya(高野山,Kōya-san?) is the name of mountains in Wakayama Prefecture to the south of Osaka. Also, Kōya-san is a modifying word for Kongōbu-ji (金剛峯寺). There is no mountain officially called Kōya-san (高野山) in Japan.
First settled in 819 by the monk Kūkai, Mt. Kōya is primarily known as the world headquarters of the Kōyasan Shingon sect of Japanese Buddhism. Located in an 800 m high valley amid the eight peaks of the mountain (which was the reason this location was selected, in that the terrain is supposed to resemble a lotus plant), the original monastery has grown into the town of Kōya, featuring a university dedicated to religious studies and 120 temples, many of which offer lodging to pilgrims. The mountain is home to the following famous sites:
Okunoin (奥の院), the mausoleum of Kūkai, surrounded by an immense graveyard (the largest in Japan)
Danjogaran (壇上伽藍), a heartland of Mt. Kōya.
Konpon Daitō (根本大塔), a pagoda that according to Shingon doctrine represents the central point of a mandala covering not only Mt. Kōya but all of Japan
Kongōbu-ji (金剛峯寺), the head temple of the Kōyasan Shingon Buddhism
Koya-san is accessible primarily by the Nankai Electric Railway from Namba Station (in Osaka) to Gokurakubashi Station at the base of the mountain. A cable car from Gokurakubashi then whisks visitors to the top in 5 minutes. The entire trip takes about 1.5 hours on an express train or 2 hours by non-express.
Local automobile traffic can be very heavy on weekends until well into the evening. On weekdays, however, the mountain offers a pleasant drive followed by the excitement upon reaching the monasteries lining the summit. Many Buddhist monasteries on the mountain function as hotels for visitors providing traditional accommodation with an evening meal and breakfast.