Mt. Sanbongui

Mt. Sanbongui (三本杭, 1,226 m), on the border of Uwajima and Matsuno in Ehime and Shimanto in Kochi, is the highest peak of the Onigajo range and one of the 300 Famous Japanese Mountains. It is also called Mt. Nametoko.
It lies south of the Nametoko Gorge, known for the Yukinowa Falls, and its summit is a rounded cap of dwarf bamboo. The draw is the view over Mt. Onigajo and Mt. Yatsuomote to the Uwa Sea, and the granite gorge scenery. The usual route is a day-trip loop from the Mannenso at the Nametoko Gorge, via the Yukinowa Falls and Senjojiki to Mt. Sanbongui. By public transport you reach the Nametoko Gorge by taxi from Matsumaru Station.

The base is the Mannenso at the Nametoko Gorge (Nametoko Outdoor Center, about 280 m); from the riverside path past the Yukinowa Falls you follow Senjojiki and Oku-Senjojiki and climb over Kuma-no-Koru to Mt. Sanbongui. The climb takes about 3 hours, and the loop descending the Hinoki ridge is about 5 hours 30 minutes as a day trip. The riverside is dangerous when the water rises after rain and the wet rock is slippery, and from early summer to autumn you also need to guard against mountain leeches.
At the trailhead the Nametoko Outdoor Center Mannenso (tel 0895-49-1535, campsite and cottages) is a base for a night before or for canyoning. The best seasons are fresh green in May and autumn leaves in November, but as a low mountain it can be climbed year-round. There is also a long route over Mt. Yatsuomote from the Nogawa trailhead on the Uwajima side, but this article covers the loop from the Nametoko Gorge.

*Information last checked: June 14, 2026

How to access the trailhead

1. [Round trip] Matsumaru Station ⇄ Nametoko Gorge (taxi)

1. [Round trip] Matsumaru Station ⇄ Nametoko Gorge (taxi)

The trailhead, the Nametoko Gorge (Mannenso), has no route bus; it is about 20 minutes by taxi from Matsumaru Station on the JR Yodo Line. Matsuno Taxi in front of Matsumaru Station (tel 0895-42-1108, a 1-minute walk from the station) is handy, and it is best to arrange your return time on the way out, as the mobile signal is weak in the gorge. Matsumaru Station is about 40 minutes from Uwajima Station on the JR Yodo Line (Shimanto Green Line). The Mori-no-Kuni bus (Matsuno community bus, 100 yen a ride) runs within the town but does not reach the gorge trailhead, so from the station it is taxi or car. By car, use the free car park at the Mannenso (about 150 spaces).

Taxi: Matsuno Taxi (tel 0895-42-1108). It is easy to share the fare by the number of passengers, so teaming up with other hikers is economical. Overnight: there is lodging at the Mannenso (cottages, campsite) at the gorge and around Matsumaru Station, handy for an early start. Check the latest taxi fares and availability with Matsuno Taxi.

Reference: [Uwajima Tourism Guide — Nametoko Gorge]

Route and safety notes

Route (loop from the Nametoko Gorge): Mannenso → Yukinowa Falls (about 40 m) → Senjojiki (about 40 m) → Oku-Senjojiki (about 30 m) → Kuma-no-Koru (about 50 m) → Mt. Sanbongui, 1,226 m (about 30 m). The climb is about 3 hours 10 minutes. Descend the Hinoki ridge back to the Mannenso (about 2 hours 20 minutes), making the loop about 5 hours 30 minutes in total. Depending on your fitness, you can also just go out-and-back to the Yukinowa Falls.

Facilities: at the trailhead the Nametoko Outdoor Center Mannenso (tel 0895-49-1535, campsite, cottages, toilets, car park). There is no mountain hut on the route, so it is a day trip; for a night before, use the Mannenso or lodging around Matsumaru Station.

The Nametoko Gorge: a scenic gorge where a clear stream runs over slabs of granite, with the Yukinowa Falls (one of Japan’s 100 famous waterfalls) as the highlight. It is also known for canyoning. The path is slippery on wet rock; after rain, take care with rising water and stream crossings.

Mt. Sanbongui summit: a rounded summit covered in dwarf bamboo, with views over the ridge of Mt. Onigajo, Mt. Yatsuomote and Yoko-no-Mori to the Uwa Sea, and in clear weather the Ishizuchi range and the Shikoku Karst.

Season and gear: as a low mountain it can be climbed year-round, but the best seasons are fresh green in May and autumn leaves in November. From early summer to autumn there are many mountain leeches, so bring salt, repellent and leg protection. The riverside is dangerous when the water rises, so do not push on in rain.

In an emergency: call 110 (police) or 119 (fire/rescue).
Check the latest with the Ehime prefectural police.

Photo by Dokudami / Wikimedia Commons, CC BY-SA 3.0