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  • Zelkova square
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  • View toward Recreation Forest
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  • Fresh green and mountain stream
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  • Yanase ceder climbing into the air
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  • Senbon-namiki
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Senbonyama Recreation Forest


Elevation  Lowest : 400m / Mainly 400–840m  / Highest : 920m (Mount Senbonyama Summit : 1,085m)

Look up to experience the breathtaking majesty of the giant Yanase cedars

Look up to experience the breathtaking majesty of the giant Yanase cedars

Newest information
Please visit official tourism websites for the latest updates and information.
movie.jpg  Drone Footage
Autumn leaf viewing Birdwatching Picnics(Park)Mountain climbing (Includes surrounding area) Areas for paddling/fishing(fishing) Cycling Guided tours(No foreign languages spoken) Forest railway(Outside the forest)(inquiries must be made in advance) Hot Spring(Outside the forest)
Geographical/topographical features
Located deep in the heart of eastern Kochi Prefecture, close to the border with Tokushima Prefecture, this is one of Kochi's foremost woodland areas. It is home to numerous mountains with an elevation in the 1000 m class.
Historical/cultural features
The remote mountain hamlet of Yanase is said to have been settled by defeated Heike warriors and has produced high-quality giant trees suited for use in building castles, shrines, and temples ever since the Sengoku period (1467–1590). Senbonyama literally means “mountain of a thousand trees” and the mountain is said to have gained its name from the innumerable trees that crowded its slopes.
As such, local feudal lords imposed a strict ban on entry to the forest or mountain by the common people. The Yanase-sugi, Yanase Japanese cedar (Cryptomeria japonica) forest that stands today on Mount Senbonyama is said to be the result of regeneration that resulted from this ban, which was imposed at a time when many of the mountain's trees had been cut down.
Climate, flora and fauna
With annual average rainfall of 4,230 mm and a maximum recorded rainfall of 6,113 mm (2004), the Yanase district rivals Yakushima as one of the nation's foremost torrential rain zones. Combined with a warm climate, this is a key factor contributing to the prevalence of giant trees in the area. Around 300 years old, the Yanase cedars have a maximum diameter in excess of 2 m, a height of 50 m, and can weigh up to 45 tons each. Even a single specimen viewed in isolation would be impressive, but Mount Senbonyama is crowded with more than 17,000 giant trees of this kind, each standing at least 25 m high. Other trees tend to be overshadowed by the Yanase cedars, but the mountain has also gained a reputation as a source of high-quality timber from not only sugi, Japanese cedar (Cryptomeria japonica), but also momi, fir (Abies firma); tsuga, Japanese hemlock (Tsuga sieboldii); and hinoki, Japanese cypress (Chamaecyparis obtusa). In total, about 120 varieties of tree grow on Mount Senbonyama.
Along with the nihon kamoshika, Japanese serow (Capricornis crispus), which is protected as a nationally designated special natural monument, the creatures for which the forest provides a habitat include nihonjika, sika deer (Cervus nippon); squirrels (Sciuridae); and saru, Japanese macaque (Macaca fuscata).
Mount Senbonyama is located in a National Forest adjacent to this recreation forest. A Mountain Trail has been laid from the Mount Senbonyama trailhead to the sumiit ot the Mount Senbonyama.
There are giant cedars all around. Beside the trailhead stands Hashi-no-o-sugi (Big Cedar of the Bridge), a giant cedar chosen for inclusion in 100 Giants of the Forest (a list of leading giant trees in national forests in each area that should be protected as part of the heritage of future generations). There is also Hachimaki-otoshi (Headband-dropper), which takes its name from the fact that, to see the very top of the tree, you have to tip your head back so far that your headband falls off. Along the trail halfway to the top of the mountain, among the numerous notable specimens visible is Mayumi-sugi, which was named for its particularly beautiful appearance (Mayumi is a woman’s name that means “true elegance and beauty”). Even those who lack confidence in their physical strength can enjoy this unique scenery, which differs so greatly from other mountains. The end halfway of the trail to the summit is a little more challenging. Nevertheless, we do invite those who are strong walkers to attempt the climb to the summit. Soaking in the hot spring (Yanase-no-yu or Umaji-onsen) located at the foot of Senbonyama after hillwalking is also recommended.
Kochi Yuzu Road is an initiative by Umaji-mura and four other Chugei region municipalities, based around the forest railway and local yuzu production. This initiative was awarded the Japan Heritage designation on April 28, 2017. At Maruyama Park in the Yanase District, visitors can enjoy a ride on the forest railway that operated in the Chugei region in the first half of the 20th century.
Please contact the Yanase-no-yu Forest Conservation Center (Tel: 0887-43-2240) to inquire about train rides.
Latest Information
There is no information on any temporarily unavailable facilities.
Events: Events in Umaji-mura include the Yanase Cherry Blossom Festival in April, the Yamashi Tatsujin Senshuken Lumberjack Festival in October, and the Yuzu Hajimaru Festival in November.
・Please note that ticks are present in this area between April and September, so particular caution is required. Wear long sleeves and long trousers.
There are places where the footing is treacherous, so visitors who lack sufficient physical strength or do not have the proper equipment should turn back at the observation platform.
This area experiences torrential rain, so visitors should keep away from the river in the event of severe thunderstorms.
Usage Guide
Entrance fee
Opening seasons and hours
Open all year. Open 24 hours a day, 365 days a year.
Accommodation options
Japanese inns are located in the Yanase district. In addition, there are hot spring hotels in central Umaji-mura.
Toilets and drinking fountains(Toilets) Toilet (accessible)(Outside the forest) Walking trail Parking lot Vending machine(Outside the forest) Shop(Outside the forest) Restaurant(Outside the forest) Campsite and/or cabins(Outside the forest)
Hozoyama Water Park (Open free of charge from April to the end of November)
Accommodation facilities (Hotels/Japanese inns)(Outside the forest)
Yanase, Umaji-mura, Aki-gun, Kochi Prefecture
(Distances and times are provided as a guide only)
By public transport
<Access from nearest railway station / bus stop>
  • ・There is no public transport or taxi service from the Yanase district to the trailhead
    From Yasuda Station to the trailhead using Taxi will take 2 hours, 45 km.
    (approx. 10 km).
〈Access from major transport hubs to nearest railway station / bus stop〉
  • ・About 1 hour 30 minutes from Kochi Station to Yasuda Station using the JR Dosan Line and the Tosa Kuroshio Railway Gomen-Nahari Line. From Yasuda Station, visitors can catch a bus bound for Umaji or Yanase, which will get them to the Yanase district in 40 minutes.
By car
  • ・Nankoku IC exit → Route 55 → Pref. Route 12 → Pref. Route 54 → Pref. Route 370 86.3 km
<Car parking capacity / parking charges>

space for around 5 passenger cars(free)

Nearby tourist facilities
  • ・Umaji Onsen hot springs (Umaji-mura), remains of the forest railway (5 nearby municipalities)
Management office contact details
Aki District Forest Office
Yanase/Nishikawa/Higashikawa Forest Administration Office
TEL : 0887-43-2314
Information on Other Local Tourist Attractions
Kochi Prefecture Mori to Midori no Kai (Forest and Greenery Association) [External link]
Official Tourist Information
Kochi Prefecture Mountain Hiking Guide: Local Tourism Division, Tourism Promotion Department, Kochi Prefectural Office [External link]
Recreation Forest Management Committee
Senbonyama Recreation Forest Management Committee

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