The Hata developed this area and later helped the court to establish the capital here in 794. Oyamakui has been called a mountain god, although that term may obscure his real identity: he is rather the deification of the pure and life-giving water that streams down from the mountain. That is evident from the Reiki no taki ("the Falls of the Holy Turtle"), a waterfall in the grounds behind the main hall, and also from the Kame no i ("Well of the Turtle"), a natural well also on the mountainside. The turtle is the messenger of the kami of Matsuo. After the foundation of Heiankyo, together with the kami of the Kamo Shrines, Matsuo-san was promoted to become one of the protectors of the capital.
The link with sake is much more recent. It only comes from the Muromachi period (when sake brewing became an industry) and was connected again with water, in the form of the belief that sake of which the brewing water contained some water from the Turtle Well in the grounds of the shrine, would never turn sour (sourness due to hiochi bacteria was a big problem for early brewers). So Matsuo-san became a protector of the craft of sake brewing, something which is still his most important function today. Sake breweries often have a small Shinto altar (kamidana) dedicated to Matsuo-san in the brewery, near where the actual brewing takes place, and at certain important times such as the beginning of the brewing year, the brewers will worship there together. Every year new amulets from the shrine are received as well and brewers often visit the Matsuo Shrine for the Jo-u Festival in November, when prayers are said for successful brewing.
But the link of sake is not with the actual founding history of the shrine (the Hata brought several new technologies to Japan, but sake brewing was not among them) - this in contrast to the other major "sake shrine," the Miwa Shrine to the south of Nara (in Sakurai), which has a deeper connection with sake, in the sense that sake figures in its foundation legend, where it is presented as a gift to mankind from the gods.
[The torii gate. At the back the Romon gate.]
The Matsuo Shrine stands immediately next to Matsuo Station on the Hankyu Arashiyama Line (running between Katsura and Arashiyama), and the approach to the shrine is brief. The main hall dates from 1397 (with repairs in 1542). An "important cultural property," it has a roof of shingles from cypress bark and long overhanging eaves in the front and back (called ryonagare-zukuri). A stream, the Ichinoigawa ("First Well River") runs through the grounds and has beautiful Japanese rose bushes (yamabuki) from mid April to early May. Two of the wooden statues of male deities the shrine owns are now "national treasures," and one female deity has been declared an "important cultural property." These kami images date from the 9th c. and are among the earliest statues of Shinto gods. They are well worth seeing.
[Iwakura no niwa, garden with huge rocks like the iwakura on top of Mt Matsuo, by Shigemori Mirei]
The shrine gardens have been beautifully laid out by one of the most famous 20th c. garden architects and garden historians of Japan, Shigemori Mirei (1896-1975). The first garden lies in front of the small shrine museum housing the kami statues and is called Kyokusui no niwa (Garden of the Winding Stream - in Heian japan such streams were used to float down sake cups and compose poetry) - it features the big upright rocks Shigemori Mirei became famous for, as well as his modern use of concrete; the second garden, Iwakura no niwa ("Garden of the Sacred Rocks"), lies next to the shrine museum and imitates the iwakura on top of Mt Matsuo, the original cult place of the shrine; the third garden (Horai no niwa or "Paradise Garden") lies to the right between the large torii and the Romon gate, behind a restaurant. It is a pond garden with standing stones, perhaps a bit less typical of Shigemori Mirei's work because of the large pond, but nonetheless beautiful; it was finished by the son of the garden architect, as Shigemori Mirei unfortunately died in the period he was working on this garden.
[The Turtle Well]
The three gardens plus the shrine museum, the waterfall Reiki no taki and the Turtle Well can all be seen together for a small fee. There is another fee to climb Mt Matsuo to view the iwakura. Thanks to its sake connection, the shrine also has a a small sake museum which in recent years has been nicely refurbished. There are old tools, cups and other implements, old labels and advertisements, etc. Entry here is free. It is to the left of the Romon, in the same building as a Mori tsukemono shop - interestingly, they have some pickles made with sakekasu (sake lees) which are only sold here.
The biggest festival of the shrine is the Shinkosai, which is held the first Sunday after April 20; it includes a mikoshi procession where one mikoshi will be boarded on a boat on the Katsura River (it will return three weeks later in a second festival called Kankosai). Other important festivals are Hatsumode (the first shrine visit at New Year), Setsubun on February 3 or 4, the Kerria (Japanese rose bush) Festival (April 10 to May 5), Oharae (Great Purification) on June 30, Ontasai (Rice Planting Festival) on the 3rd Sunday of July, Hassakusai (Harvest Festival) on the first Sunday of September, and the above-mentioned sake brewing prayers on the Jo-u day (old calendar) in November (thanksgiving for successful brewing is likewise held on the Chu-yu day in April).
Immediately next to Matsuo Station on the Hankyu Arashiyama Line. Or take bus 28 or 73 from Kyoto Station; bus 63 from Sanjo Keihan Station.
Read more about this and other Shinto shrines in: Shinto Shrines, A Guide to the Sacred Sites of Japan's Ancient Religion by Joseph Cali and John Dougill (University of Hawai'i Press).
Japanese materials: Nihon no Kamigami, Jinja to Seichi edited by Tanikawa Kenichi (13 vols, Hyakusuisha). Shukan Jinja Kiko (50 vols, Gakken). Kyoto Yamashiro Jiin Jinja Daijiten (Heibonsha).