Mountains · Yamagata
Gassan
月山がっさんGassanThe moon mountain of the Dewa Sanzan, realm of the dead and of summer snow.
Gassan (月山, "moon mountain"), 1,984 m, is the highest of the Dewa Sanzan, the three sacred mountains of Yamagata Prefecture. Its summit shrine venerates the moon deity Tsukuyomi, and in the Shugendō pilgrimage of the Dewa Sanzan it represents the past life – death – on the path to rebirth.
Overview
Gassan rises as a broad, gently sloping dome in the centre of Yamagata Prefecture, between the Shōnai plain and the Murayama basin. Its mild shape belies its climate: exposed to the full force of the Sea of Japan monsoon, it carries one of the deepest snowpacks in the world, and snowfields persist all summer.
With Haguro-san and Yudono-san it forms the Dewa Sanzan, one of Japan's great Shugendō centres. For centuries yamabushi mountain ascetics in white robes and conch-blowing pilgrims have crossed it on the way from Haguro-san to Yudono-san. Gassan represents the world of the dead: pilgrims believe that ancestral spirits dwell on its slopes.
Landscape and formation
Gassan is a volcano that was active roughly from 1 million to several hundred thousand years ago and is now considered extinct. Its broad form results from lava flows spreading over a gentle base; glacial and snow erosion carved the steep eastern side, where the Ubazawa valley holds late snow.
The western slopes above the Hachigōme are a vast wetland plateau, Midagahara, with hundreds of small ponds (ikeshūsu) on the peat.
Highlights
Gassan Jinja summit shrine
月山神社本宮Gassan Jinja hongūThe inner shrine of the moon deity Tsukuyomi on the summit, enclosed by stone walls against the wind.
Midagahara
弥陀ヶ原MidagaharaA high moor at the eighth station with wooden walkways and hundreds of pools.
Ubazawa
姥沢UbazawaThe snow-filled valley on the east side with the Gassan ski area.
Yudono-san
湯殿山YudonosanThe third of the Dewa Sanzan, south-west of Gassan, whose sacred object is a hot spring rock; photographs are forbidden at the shrine.
Ecology
Heavy snow keeps the treeline very low, around 1,400 m, so meadows and bogs cover a large part of the mountain. Snowbed flowers bloom in waves as the snow retreats through summer.
Flora
Kuroyuri
クロユリkuroyuriThe dark chocolate lily, Gassan's symbolic flower, blooms near the summit in July.
Nikkō-kisuge
ニッコウキスゲnikkō-kisugeYellow day lilies on the Midagahara moor.
Beech
ブナbunaSnow-bent beech forests on the lower slopes.
Fauna
Asian black bear
ツキノワグマtsukinowagumaCommon in the beech forests of the Dewa Sanzan.
Golden eagle
イヌワシinuwashiSeen over the Asahi and Gassan ranges.
Culture
According to tradition, Prince Hachiko, son of Emperor Sushun, fled to Dewa in 593 and was led by a three-legged crow to Haguro-san, founding worship of the three mountains. The Dewa Sanzan pilgrimage – Haguro for the present, Gassan for the past, Yudono for the future – is a symbolic journey of death and rebirth, and yamabushi still undertake the autumn peak (aki no mine) retreat. In 1689 Matsuo Bashō climbed Gassan and wrote "Kumo no mine ikutsu kuzurete tsuki no yama" – "How many cloud peaks have crumbled to leave the moon mountain".
Dewa Sanzan Jinja
出羽三山神社Dewa Sanzan JinjaThe combined shrine on Haguro-san, where the deities of all three mountains are worshipped in winter.
Hagurosan five-storey pagoda
羽黒山五重塔Hagurosan gojū-no-tōA national treasure among giant cedars on the stone-stepped approach to Haguro-san.
History
593
Traditional founding of Dewa Sanzan worship by Prince Hachiko.
1689
Matsuo Bashō climbs Gassan and writes his haiku.
1950
Bandai-Asahi National Park is designated.
Through the seasons
Spring
The mountain is under deep snow; the ski area opens around April and spring ski touring is popular.
Summer
The summit shrine opens and pilgrims and hikers arrive; skiing continues on the Ubazawa snowfields into July, and flowers bloom from July.
Autumn
Colours on the upper slopes in late September; the summit shrine closes for the winter.
Winter
Among the deepest snow in the world; access roads close and the mountain is left to the gods.
Routes and trails
Hachigōme route
From the Midagahara moor at the eighth station, about 2.5–3 hours up through meadows and rock; moderate, the old Haguro pilgrims' route.
Ubazawa route
From Ubazawa by chairlift and then via Ushikubi, about 2.5 hours; moderate, with snowfields well into summer.
Gassan to Yudono-san
The pilgrim descent from the summit to Yudono-san via iron ladders along a stream, about 3 hours; steep.
Practical notes
- The Hachigōme and Ubazawa trailheads are reached by seasonal buses or car from Tsuruoka and Yamagata; access roads close in winter.
- The summit shrine requires a purification offering before entry; photography inside the shrine enclosure is not allowed.
- Snowfields and fog make navigation difficult; follow the marker poles.
- Bears are common in the lower forests.
Frequently asked questions
How long does it take to climb Gassan?
From the Hachigōme (eighth station) at Midagahara the summit is about 2.5–3 hours; from Ubazawa with the chairlift about 2.5 hours. Both routes are moderate walks through flower meadows.
What are the Dewa Sanzan?
Haguro-san, Gassan and Yudono-san, three mountains near Tsuruoka that have been a centre of Shugendō since, by tradition, Prince Hachiko founded worship there in 593. A pilgrimage over all three symbolises present, past and future lives.
Can I ski on Gassan in summer?
Yes. Because the snow lies so deep, the Gassan ski area opens only in spring, around April, and operates into July – it is closed in mid-winter.
Is the summit shrine open all year?
The Gassan Jinja summit shrine is open only in the summer season, roughly July to mid-September; visitors undergo a purification rite before entering.
Related
Sources
- 1.日本の主な山岳標高 (opens in a new tab) — 国土地理院 (Geospatial Information Authority of Japan)
- 2.磐梯朝日国立公園 (opens in a new tab) — 環境省 (Ministry of the Environment)
- 3.山形県ホームページ (opens in a new tab) — 山形県 (Yamagata Prefecture)