Trail running in Japan

Please scroll down to read about clubs, heat and humidity, clothing and equipment, radiation, safety and dealing with wildlife and more...last updated Jan 2024

Japan is a mountain runner's paradise as around 74% of its area is covered with mountains. Most, apart from the highest are wooded to the summit, so views are often limited, but even the smallest can be very beautiful, wild and rough. Many have Shinto shrines and Buddhist temples, and you may come across statues of Yamagin - ascetic monks who lived alone in the hills. Even cities often have mountains close by, and these are usually well served with networks of marked trails, as are famous hiking areas. Most other areas have at least some trails, which will vary from good hiking trails, to forestry roads, to sketchy paths (used for gathering wild food or hunting), which peter out. Japanese people often do linear routes using buses and trains, and circular routes can be harder to find. The basic pattern for Japanese mountains is steep sides and long, sharp, undulating rides. The structure of the land is often complex. Paths vary from root and boulder-strewn obstacle courses requiring a lot of concentration, to flights of steps, to fast sandy gravel or forest roads.

Japan's highest mountain is national icon Mount Fuji at 3,776.24 m (12,389 ft), but size isn't everything, and it is a long slog you may not want to repeat. The Japan Alps (Northern, Central and Southern) include the next highest and bisect Honshu, Japan's main island. Hokkaido to the north contains many large mountains and wide open spaces. There are of course many active volcanoes in Japan. Please note that much of the northern half of Honshu was contamminated by radiation from the ongoing Fukushima nuclear disaster (see the useful links list for maps of air and soil contamination). Please inform yourself before travelling.

Vocanic caldera lake

The trail running scene in Japan
Trail running in Japan (or 'trailu lunningu' as it is roughly pronounced) is a catch-all term often used to cover all off-road running. It makes sense as because of the forests and roughness, running off the trail is usually impractical. It includes what might be known as 'fell running' in the UK,  'mountain running' or 'trail running' elsewhere. The overlapping disciplines of cross country (in parks), adventure racing (multi-dicipline including trails) and orienteering (micro navigation at speed) also exist, along with Rogaining (orienteering over ultra-distances). Obviously road running (now wash your mouth out!) is very popular in Japan, and high school and university relays get huge TV audiences, so strangely, even children will cheer you on rather making fun.

Trail running is a relatively new and undeveloped sport in Japan except in Kanto (the mountain-rimmed plain around Tokyo), where there are clubs and more races. In other areas there are scatterings of individuals who do it, and the races can be full well in advance, but people usually do it on their own and there are very few specialist clubs.  As yet there is no unifying national association for clubs and races like the UK's Fell Running Association. A common model for a 'club' is a commercial venture run by shops. Members are 'customers,' there is often a fee on the model of a school with organised 'events,' or as you or I might call it, 'going for a run.' Ho hum.

At the moment ultra-distance trail races are booming, which is odd as the average very hard working Joe has hardly any spare time left for training. Trail races are usually expensive and also run by businesses, possibly  because long working hours equally mean there is less time for amateur activity.

Trail running clubs in Japan

Here are a few clubs I have come across, let me know if you find more and I will add them:

Tokyo and the Kanto region:

• Tama Orienteering Club, Tokyo -  proper club, also do trail training/racing. My mate Taku-san runs it and he's bi-lingual and friendly. For information or assistance on orienteering/trail running (especially near Tokyo): tama■orienteering.com (■＝ @)
• Namban Rengo, Tokyo - informal bi-lingual club doing all disciplines including trail
• Tokyo Trailrunning Facebook group: seem to be a 'school' providing guided runs, probably with a charge (thanks to Anastasia for letting me know about this one)

Kansai: 

• MRHC(Mt.Rokko Hard Core) Ashiya, Kobe.Training: Most Thursday nights near Ashiyagawa trail,  2 & 1/2 hours road and trail running, from 8PM to 10:30PM. Details: Sky High Mountain Works- shop-based club tel 0797-34-3299 (owner Taku-san speaks basic English)

The seasons in Japan
Whilst it is possible to enjoy running in some form all year round, the nicest seasons to trail run in Japan are spring and autumn. The winter can also be great for running (outside snow country), as it is often dry and bright - though cold - and the lack of foliage means there are more views in the woods. The snow country (mountains towards the Japan sea side of the country on Honshu) gets prodigious amounts of deep, soft snow, up to a metre day or more, is prone to avalanching, and running is only possible in winter on quiet ploughed roads. The eastern, Pacific side gets relatively little snow. Hokkaido gets very cold, Siberian style weather in the winter. Okinawa in the south west is relatively warm all year round.

Quiet ploughed roads - the only practical option in 3m of soft snow

Heat and humidity
From June (the rainy season) to September Japan can be very hot, usually over 30c in the afternoon, sometimes into the 40s, and sometimes as hot as 48c as it was in my village in Fukushima one day. However, what makes it most difficult for trail running (as for everyday Japanese folk) is the crushing humidity on top of that, which can be very exhausting, especially if you haven't acclimatised. You can be dripping with sweat just sitting down inside in a t-shirt and shorts - now imagine running up a hill. In recent years a lot of people have died of heatstroke, mainly older people working in the fields. Most Japanese races are programmed outside July and August for this reason.

Classic Japanese mountain terrain, summer

I know we are all roughty-toughty trail runners, but heat needs to be taken seriously. Please do your own research and try what works for you. It may be obvious, but this is what I tell myself:

• Avoid running in the afternoon unless I am at an altitude where it will be cooler. 5am to 10am is the 'coolest' part of the day (but be aware of wildlife at this time- see below)
• Carry plenty of liquid and keep well hydrated before, during and after running (latterly I am finding that isotonic drinks work well when sweating reaches extreme levels). I very rarely carried drinks fell running in the UK, but in Japanese summers I usually plan for about 750ml per hour when it is bad, so it isn't uncommon to have a full 2 litre bladder plus bottles on a long run. I carry change for drinks machines - but don't bet on their being one, even on popular tops with roads to them. Sods law applies. I sometimes come across deliciously cold spring water which is prized by the Japanese. Water the locals drink is identifiable by the cups that are usually placed by them. Some Japanese drink out of open mountain streams, and on occasion I have too (I follow the usual precautions and have been lucky so far), but I won't now in East Japan (Kanto up), except in extremis, because of radiation. As is true around the world, there can also be nasty viruses in Japanese streams. If in doubt, don't - or use a proper water purification kit. 
• Cover up. heat stroke is bloody awful, so I wear a peaked hat (I am a slaphead), sometimes with a neck flap as well. I wear white man-made fibre t-shirts rather than vests as shoulders really catch the strong UV. I now wear man made fibre as I am always completely drenched in sweat in the summer, and it handles it better than cotton.
• Take it easy. Even elite runners cannot move as fast when it is hot and humid. Expect to take from 30-100% longer for a given route than in the cool. Don't take it personally!

Some people like to use insect repellent, though I haven't found they bother me too much when running, just when I stop sometimes. I am clearly repellent enough already.

Clothing and equipment

Please make your own judgements, This is just an idea of my own typical trail running kit-list in Japan.

Absolute minimum (eg for busy bear-free areas, or races with aid stations, outside winter, with a companion). In my opinion if you take less than this you are asking for trouble - why take the risk for the sake of a few grammes?:

• Peaked cap for sun and a little eye-protection from twigs
• Bumbag (waist pouch) or running sac with hydration pack if hot
• Full waterproof body cover (even if it is hot it is handy to be able cover up if immobile because of insects and for leg protection when thrashing through bamboo)
• Liquid, energy gels and food as needed (I never go with nothing, just in case)
• Map and compass unless it is a familiar route
• Mobile phone (Docomo has best mountain coverage, but I don't rely on it - many mountains and valleys have no coverage) 
• Bear bells, but please also see bear section
• Money and ID

+ When running alone / in wild areas / bear country I usually add:

• Bear pepper spray instantly accessible (not inside a bag) unless racing
• Additional food, drink and clothing for the weather conditions
• A first aid kit

+ At colder times of year in wild country I might add:

• A bigger running sac
• A warm hat and gloves
• Extra spare clothing layers including leg cover
• A survival bag or lightweight racing tent (for emergency nights out)
• A lightweight sleeping bag

Late autumn in bear country: spray in a chest pouch, bells, full 25 litre rucksac

If you want to fit in with the gear-obsessed natives, the current fashion is for compression tights or socks (even in summer) with baggy knee length shorts over the top, hi-tech tops and arm warmers, with gloves for protection against scratching, all preferably branded, dedicated running gear - no cheap substitutes (Unlike my ¥100 shop accessories above!).

Navigation

Also see safety below. Navigation in the thick woodland that covers most of Japan's mountains is difficult. Some trails in popular areas are marked, with suggested times, but don't rely on them consistently being there will likely be in kanji characters. Having at least two navigation options is advised: a GPS device or smartphone with pre-downloaded maps, remembering that mobile phone/data signals will not be consistently available, if at all in the mountains. And always carry a paper map and compass, either the Mapple Yama Chizu series, or one printed from the zoomable government mapo resource here using the instructions here. Technology fails and rescue in the Japanese mountains is unlikely.

 

Prepare your maps before leaving home for a run. Don't wait until arriving somewhere to look for a map in a visitors centre or similar. They often don't have them, or have nearly useless leaflet with cute diagrams bearing little relation to scale or orientation. Japanese maps on boards and leaflets often do not have north at the top, so think what you are looking at first. Take a magnifying glass so you can match the tiny kanji characters on your map to those on boards and signposts.
 

Shoes for trail running in Japan
There is often a wide mixture of surfaces on Japanese routes, so the optimum sole can vary:

• Light road-race-style trail shoes with a light grip, for example with courses including some road and concrete tracks on dry days (OK if you know what you are doing and are going fast enough to prioritise lightness over grip -  I wouldn't use them myself))
• Trail shoes with a medium grip for a bit of everything (the most popular kind with Japanese runners and what I am using in Kansai)
• Deep studded mountain/fell shoes for very rough steep terrain (especially in the wet) and deep slippy leaf litter. (What worked best for me in Okaizu where it was quite technical - there were few freely runnable tracks)

Health and Safety
I don't want to put you off, or seem over-cautious but there are a few things worth knowing about trail running in Japan that ou might not have come across before. Remember that, scary as the following might seem, there are thousands of Japanese people working in the mountains every day in forestry, picking wild food, tending mountain rice paddies and allotments, working on civil engineering projects, or like you, just there to enjoy them. It is relatively very unusual to have a problem, but it pays to be informed, equipped, insured, and careful. There is no substitute for good judgement.

The following are some of the things I consider myself when running in Japan and in no way constitute a recommendation for a particular course of action - as always you are solely responsible for your own safety on the hills and need to do research for yourself. Please also check your country's travel and medical guidance for visiting Japan.  I am not an expert.

Telephone number for emergencies (as of 22.2.13): medical and fire emergencies: 119. Police is 110 but is usually only used to report crimes.

I try and follow the usual international mountain safety guidance, and if you don't know what that is don't go on the mountains until you do. In addition, when running in Japan I usually bear in mind the following:

• Tell someone where you are going and what time you plan to return, and leave as detailed a route description, map or gpx as possible. (but see below on the likelihood of rescue)
  
• Keeping to clear, well-used trails - I am all for adventurous lines when I run in the UK, but going 'off-piste' in Japan can get you lost and into a lot of trouble in dense undergrowth on steep ground, sometimes disguising cliffs. I have tried it and it is really not worth it. If a path peters out, follow it back to where you last knew where you were.
• Using a map and compass (or a GPS, but only if you have maps with the paths reliably marked and know how to use it properly inconjunction with a conventional map and compass - last time I was guided on a run by someone with a GPS we got lost. A smart phone GPS with an arrow in the middle of a blank green with no contours is not going to help much). Woodland navigation is like being in thick mist all the time - you can't see the form of the land or nearby features. It is very deceptive. There is no substitute for knowing how to use a map and compass. See here for why. The Mapple 'Yamachizu' series cover many popular areas, or see link to online map, right.
  
• I assume I will not be rescued - I behave accordingly, especially if I am alone, taking fewer risks and more equipment. What do I need with me to survive? The terrain is usually very complex and wooded, no-one may hear your emergency whistle, and very few areas have specialist mountain rescue teams with dogs (though the police and volunteer fire service will try their best), and there is often no mobile reception. For example someone went missing near my village in Fukushima. They were found 5 days later, dead. Several locals who knew the terrain later went missing at different times while collecting wild food or walking and were never found. If you are lucky enough to be promptly rescued, you will have to pay. Be prepared!
• I am heat-stroke aware. When it is hot and humid I try and start early, go slowly uphill to avoid my head exploding, and avoid running in the early afternoon, I carry plenty of water, wear a sun cap or hat, and use strong sun cream.

Serious terrain masked by vegetation - that's a path at the top

Radiation
I was living in Fukushima at the time the nuclear crisis began, and self-evacuated to Kansai to get my son away after 6 months of trying to get to grips with the issue, so this is something I take very seriously.

I am not an expert, and I advise you to compare and contrast information from your own and the Japanese government, along with independent media and the very importantly the internet. There is  a huge range of opinion out there, but the nuclear industry globally has a very bad track record of covering up, and the science of low dosage effects is as yet uncertain - as acknowledged in respected peer reviewed publications like Nature and the British Medical Journal. Children and young women seem to be most at risk, men over 50 less so. Unfortunately we will not know the full effects of Fukushima Daichi for many years and they will doubtless be argued over. Very few people in Japan trust government or offical information regarding nuclear issues as they were found in official investigations to have badly misled the public.

Things to consider include:

• The air, soil and water levels of radiation in the area you intend to visit, especially in the eastern half of Japan from Mt Fuji, across Kanto and Nagano, upwards to the north and east as far as Aomori. Because of the weather some mountains have higher levels and hotspots which have not yet been fully mapped. The mountains to the north west of Fukushima Daichi, were tested by individuals and found to have quite high radiation at higher elevations probably because the plume hit them at that height. It would be a bad idea to drink water from rivers there, or to eat wild food.
• Food and drink: many people now try and source food and drink from west Japan, especially if they have children, or are young females. If you do not read Japanese you will need the help of someone who can if you are concerned and want to do this.

There are runners in Fukushima prefecture who are still running there every day and eat local food. The radiation from Chernobyl on some mountains in the UK and Europe may be at similar levels, so you may have already run in such an area without knowing. Everyone needs to inform themselves as best they can and make their own choice.

 

Citizen science soil radiation level maps are available here (please note that these maps show Cesium137 levels. Other, more long-lasting radionuclides are also present)

https://www.sortirdunucleaire.org/IMG/pdf/citizens_u2019_radiation_data_map_of_japan_1_.pdf

 

Air radiation map from citizen testing is here:

https://map.safecast.org/?y=37.65&x=134.7&z=6&l=0&m=0

Illness and infection

I am not covering this here - but  obviously check what shots you need before coming and research for yourself, for example tick-borne encephalytis and Japanese encephalitis spread by mosquitos. For more see here: https://www.fitfortravel.nhs.uk/destinations/asia-east/japan

Dealing with Japanese wildlife

Note: I am not an expert - again, please do your own research and take precautions accordingly.

Japanese Giant Hornets
The main risk from hornet stings is anaphylaxis and I imagine you will know pretty quickly if that happens. The Wikipedia page on Japanese hornets claims "On average 40 people die every year of anaphylactic shock after having been stung, which makes the Japanese giant hornet the most lethal animal in Japan, as bears kill about ten people and venomous snakes kill five to ten people each year."

A dead one - they can be big!

However most people stung don't die, it is just bloody painful. I have been told the following by Japanese people, who are very wary of them:

• "They are attracted to black clothing"
• "If you see one move slowly away - don't wave at it" 
• "If you get stung, go to the hospital."

I have seen them flying and heard the buzz of nests and moved away, and have been warned off paths by locals who have seen them. Strangely, they don't worry me as much as they probably should. I overheard a boy telling his mate "I was stung by a hornet, and I rushed to the hospital, but they kept me waiting a long time. I said 'Why did you keep me waiting so long, hornet stings are dangerous you know!' The doctor said, 'Well, if you were going to die, you would be dead before now."

Bears in Japan
There are Asiatic Black Bears in most mountainous areas of Japan. Hokkaido also has larger Ussuri brown bears. They are apparently particularly dangerous when surprised, when with young, and in the spring when they are hungry having woken up from hibernation, and in the autumn when trying to top up their fat stores for the winter. They can even wake up if you pass too close to their hibernation den. Although in some areas there are very few, potentially you can be unlucky and meet one anywhere, at any time of the day or night. Some people are attacked and killed, some survive, and many people go through life never seeing a bear once. Attacks are increasing, possibly due to reduced food and habitat; and the shrinking population meaning that bear/human boundary is getting closer in to inhabited areas as mountain allotments are abandoned. In 2023 there were 212 attacks, with 6 fatalities.

 

I have seen bears on mountain roads at 9pm, at noon by a riverside near well-used allotments, and in villages right outside people's front doors (including ours), but not on a run yet, though I have seen plenty of signs (footprints, crap, nests in trees and claw marks). So tell me punk, do you feel lucky? When you are running, you may surprise one as you are moving faster. They don't like being surprised. They can run faster than you, and black bears climb trees.

Call me stupid, but I don't let it stop me running. This is what I do in bear areas to be careful:

• I ask locals about the bear situation where possible
• I am vigilant, I look ahead, around and behind, especially in the early morning or dusk or where there is a lot of cover by the path.
• I carry a powerful proper bear pepper spray where it is instantly accessible - not in a pack or bumbag. If a spot feels 'bearish', I have it in hand. Note: these can't be taken on aeroplanes or shipped by normal means, so have to be bought (about ¥10,000) from a Japanese outdoors shop and left when you leave. They are a powerful weapon and need to be handled with a lot of care - mine went off by mistake for half a second when twigs flicked off the safety and depressed the trigger. It was very painful, and it irritated the eyes and skin for hours afterwards.  
• I shout loudly and clap every couple of minutes (sound doesn't carry far in the woods or round corners) especially when approaching an area of dense undergrowth
• I carry bear bells - not as annoying as teeth in the neck
• If it feels somehow 'wrong' I turn back
• I plan what I will do if I meet a bear. If it hasn't seen me I hope to get the safety catch off my spray and hold it aimed while keeping the bear in view (but not looking it in the eye) and move slowly and quietly away, then go a different way, checking behind in case it is following. If it has noticed me and doesn't move away I might talk, and hold my hand up to identify myself as human. If it gets within a few metres I will spray it according to the instructions with my spray. I will definitely not get my camera out first!

But there is a lot of conflicting advice out there, so who really knows? You decide. I haven't met a bear on a trail yet, but my mate has recently - it moved off. A man was attacked in our village near his house, but fortunately it wasn't too serious.

Black bear sleeping platform - note the leaves and broken branches

Venomous snakes in Japan
You will see snakes when trail running in Japan, but most of them will be harmless. According to this site there are 6 kinds of poisonous snakes in Japan, but in any given area there are unlikely to be more than a couple to remember. The Mamushi, a viper with a mottled reddish brown diamond pattern is in most areas of Honshu and you often see warning signs. It would be pretty unlucky to actually step on a poisonous snake, but they are around (one moved off the path just in front of me, and my mate nearly stepped on one recently), so I try to be careful. Most Japanese runners I have spoken to apparently don't think about them much. Please do your own research and make your own judgement.

• I learned what the few poisonous ones look like  - most Japanese snakes aren't poisonous
• I am vigilant and look where I am putting my feet and hands, and where I sit. Planting a stick/walking pole well ahead of the feet can make them more visible as they are more likely to move before you get there, but running with a pointy stick is a bad idea - as your mum has probably told you a million times.

Wild boar in Japan
Japanese wild boar are everywhere except some northern 'snow country' areas that get very deep snow for a few months. They are known to sometimes attack people when surprised, with young, or cornered, but it seems to be very rare for attacks to be fatal. The males can give you serious slashes with their tusks, and the females bite - a visit to the doctor afterwards would be advisable because of possible infection. Signs of wild boar are the dug up earth you will see nearly everywhere, scrapes for sleeping, muddy wallows, and a strong smell. A bit like English fell runners really. (Update: recently had 2 close boar encounters in one run - they were big males, quite scary) If in doubt, climbing a tree and shouting until they move on is an option.

Monkeys
Japanese macaques are fairly common, and can be seen in groups of up to a hundred in areas with high monkey populations, though usually less. Monkeys can be a pest if they are used to people (eg in tourist traps, which you'd be best advised avoiding for running anyway) and if they can see your food, which they can grab. They raid people's allotments during the day. You'd probably be very unlucky to have a problem, and the worst they tend to do anyway is bite and scratch, but you may feel intimidated as they look pretty fierce, and they are wild animals. If in doubt, I turn back, which I have only done once when about a hundred were fighting noisily all across the hill and they were not for moving when I approached. However, if I did get bitten or scratched I would definitely visit the doctor because of serious viruses. Personally, I love to think there are monkeys in my local hills and they look fantastic as they scatter through the trees. As with all the above, making noise as you go, being aware, and backing off when necessary will reduce problems.

You think I don't know about that banana in your bag pal?

Tics, leeches, centipedes and spiders

• Ticks: As in most places in the world, ticks can carry nasty illnesses like Lymes disease. Reader Joe reminded me that if a rash develops in a ring around the bite you should seek medical help immediately. In Japan, tics can carry a very serious kind of encephalitis passed on from pigs and boars. The advice I have seen is always check for them (including in your soggy nooks and crannies!) and remove in the correct fashion.
• Leeches: Leeches apparently can latch onto you when crossing damp or wet places. I have never seen one, but a friend has had them latch on. I'm told a flame or salt will make them let go. A note from reader Joe: "Don't pull them off or the teeth will stay stuck in, and the wound can get infected. Even if you don't have fire or salt, when the leech is full it will let go and drop off (disgusting I know, but safer than pulling)."
• Centipedes: Japanese Giant Centipedes (Scolopendra subspinipes mutilans) known as mukade can grow up to 20cm (8") long and deliver a very painful 'bite,'  which can cause fatal anaphylactic shock in some people. They are active at night, so check your shoes, clothing and bedding if camping. During the day they hide under logs and rocks, so be aware when resting. Do not handle! I have caught small ones in my flat with a glass and a card and put them outside.
• Spiders: Although there are poisonous spiders in Japan they have never been mentioned to me by locals, and I have run through a million spiders webs (sorry chaps, all that work, I know). There have been a few reports of dangerous Australian redback spiders being seen near Osaka airport and in Fukuoka - presumably escapees. As with snake venom, hospitals have anti-venoms for most local wildlife.

It's stating the obvious, but it's all about taking sensible precautions while enjoying the freedom of trail running, and increasing your odds of not having a problem while getting stuck into this great sport.

Please let me know if you want to suggest an amendment or addition to this page. Happy running!

Geoff Read