JGCA

Mt. FujiWorld Cultural Heritage-Objects of faith and sources of art-

Japan Geotechnical Consultants Association

INTRODUCTION.
The word “Mt. Fuji” has special
resonance for Japanese. Mt. Fuji is Japan’shighest mountain, standing 3,776 meters
above sea level and locating in both
Yamanashi and Shizuoka prefectures. Its
graceful appearance is known both in Japan and abroad as a symbol ofJapan, and it has been the subject of numerous works of art and has had
a great influence on Japanese culture.
How much do we know about such Mt. Fuji?
Let’s learn together through this booklet.
● Mt. Fuji is a cultural heritage

On June 22, 2013, Mt. Fuji was registered as a World Heritage Site
by UNESCO’s World Heritage Committee under the title, “Mt. Fuji Object of Faith and Source of Art”.
In addition to its scenic beauty as a famous mountain, its value has
been recognized around theworld as an object of worshipsince ancient times and as asource of numerous works ofart. The 25 sites recognizedas cultural heritage include
not only the mountain itself,
but also surrounding shrines,

Fuji from Miho- no- Matsubara(Yamanashi Tourism Promotion
Organization HP)

mountain trails, caves, lakes,
and marshes. Mt. Fuji viewed
1

from Miho-no-Matsubara creates a wonderful sight in harmony with thepine forest.
Why is Mt. Fuji a cultural heritage site rather than a natural heritage
site? It is said that it is because of the following reasons:(1) Several independent peaks with similar conical shapes are alreadyregistered.
(2) More active mountains are registered as active volcanoes.
(3) The original nature has not been preserved because it has beenused too much by humans.
(4) There is a lot of garbage and the toilets on the trail are not wellmaintained.
● Mt. Fuji and Faith

Mt. Fuji has been an object of faith and worship since ancient times,
as the Japanese considered its repeated eruptions to be a terrifying andmysterious mountain. Around Mt. Fuji, ruins as a result of the Fuji
worship have been found that are thought to have been created during
the Jomon Period (710-794). In the early Heian period (794-1185),
Sengen Shrine was built to calm the repeated eruptions, and in thelate Heian period (794-1185), it
became the center of Shugendo,
a unique Japanese religion thatcombined mountain worship with
Buddhism and other religions.
In the Muromachi period (13331573), a mountain trail was opened

the inner sanctuary of Mt Fuji
(Fuji Hongu Sengen Taisha HP)

and the mountain became known2

to the general public as a place to climb for worship. During Edo period(1603-1868) people began to gather to pay homage to Mt. Fuji.
● Fuji Radar

Learning from the Typhoon Isewan in 1959, a plan was madeto install weather radar at the top of Mt. Fuji for early detection of
typhoons. The construction was difficult due to the lack of roads totransport materials and the severe weather conditions in the area where
the radar was to be installed. But it was completed in 1964 and has
served as a fortress for typhoon monitoring. In recent years, it has
become possible to observe typhoons using meteorological satellites,
and in 1999, after 35 years of operation, it came to an end. The radar
was dismantled from the top of Mt. Fuji and is now open to the public in
Fujiyoshida City as the Fuji Radar Dome Museum.
Jiro Nitta, an official of the Japan Meteorological Agency at the time
who was in charge of radar construction, depicted the construction of
the radar in his novel “Fuji Summit. Later, it was made into a movie by
Ishihara Promotions, and in 2000, it was featured in NHK’s “Project X”.

Fuji Radar (JMA HP)

3

● Fuji is an active volcano

In the past, volcanoes that were still smoking were called “active
volcanoes,” dormant volcanoes were those that had erupted in historicaltimes but were not currently smoking, such as Mt. Fuji, and volcanoes
which has no records of eruption in historical times were called “extinct
volcanoes.” However, since the eruptions of Meakan-dake in Hokkaido
and Kiso Ontake, which were considered extinct volcanoes, and Akita
Komagatake, which was considered dormant, it became common
to consider all volcanoes that have a record of eruption or have thepotential to erupt in the future as active volcanoes. Mt. Fuji was changed
from a dormant volcano to an active volcano, and the terms dormant
volcano and extinct volcano are no longer used.
The definition of an active volcano has changed little by little overtime, but in 2003, the Volcano Prediction Association defined an active
volcano as “a volcano that has erupted within the past 10,000 years or
has active fumarolic activity at present. As of May 2014, there are 110
active volcanoes in Japan.

Illustration of the Hoei Eruption, October 4, Hoei 4(Shizuoka Prefectural Library)41. HISTORY OF THE BIRTH OF MT. FUJI
Mt. Fuji is a “stratovolcano” formed by conical layers of lava,
volcanic ash, and scoria (black pumice). With a volume five times that ofa typical stratovolcano, it is the largest volcano on land in the Japaneseislands.
● Foundation of Mt. Fuji

What is the interior of Mt. Fuji (Shin-Fuji Volcano)? It is believedthat Old Fuji Volcano and Komitake Volcano are buried within Mt. Fuji.
Recent research suggests that an even older pre-Komitake Volcano isburied beneath the Komitake Volcano. There is Ashitaka Volcano to thesouth of Mt. Fuji. Mt. Fuji is a multi-story volcano based on these older
volcanoes.
Let’s take a look at the history of the volcanoes that formed thefoundation of Mt. Fuji. About 200,000 years ago, Mt. Ashitaka and
Mt. Komitake volcanoes erupted repeatedly. About 100,000 years
ago, these volcanoes ceased their activities and were replaced by OldNew Fuji
From 10,000 years ago.
old Mt Fuji
till 100,000 years ago.

southsmall mountaintill 100,000 years ago.
Mt. Aitaka
From 40 to 100 thousand
years ago.

Mt. Senkmonidake
Some 100,000 to 200,000 years ago.

Fuji’s interior (Fujii, 2013)
Illustration of the Hoei Eruption, October 4, 1704
(Shizuoka Prefectural Library)

5

north

Fuji volcanoes. The Old-Fuji volcano repeatedly erupted explosively,
spewing large amounts of ash and scoria into the air and forming thefoundation of Mt. Fuji.
● Eruption of New-Fuji Volcano

Around 10,000 years ago, the New Fuji Volcano began its activity
on the slightly western side of the summit of the Old Fuji Volcano. New
Fuji Volcano repeatedly erupted in relatively quiet eruptions, with lava
flowing from both the summit and flank craters, and explosive eruptions,spewing a lot of ash and scoria from the craters. Lava at the beginningof the New Fuji volcano is flowable, and some lava has been found tohave flowed down as far as 40 km.

Western calendar

After the last eruption 2,200 years
Jogan eruptionago, eruptions from the summit

Massive lava
flow released

crater of New-Fuji Volcano ceased,
and only eruptions from the flankcraters have been occurring.
Fuji is known to have erupted
about 10 times in the historical
record, with the Jogan eruption of864-866 during the Heian period

Hoei Eruption

and the Hoei eruption of 1707

Massive lava
outpouring,massive eruption
lasting 16 days
Ash fall in Edo(Tokyo)during the Edo period being themost significant.
In the Jogan eruption, 1.3 billion

Eruption of Mt. Fuji in the historicalperiod(Fujii, 2013, drawn from Koyama 1998)

cubic meters of magma overflowedfrom two lines of fissure craters
6

Pacific Ocean

Mt. FijiLake Motosu

Lake Sai

Aokigahara Lava
Lake Shoji

Aokigahara Lava (Fuji Five Lakes TV HP)

at the northwestern foot of the volcano, and lava flowed down the footslopes of the volcano. This is the Aokigahara Lava. The Aokigahara lava
flowed into Motosuko and then large lake called Senoumi, and filled up
Lake Senoumi, dividing it into the current smaller lakes of Shojiko and
Saiko. This eruption continued for about two years.
The Hoei Eruption was an explosive eruption that spewed out 1.7
billion m3 of volcanic ash and scoria (700 million m3 of magma) in only
16 days, creating a crater larger than the summit crater on the southeast
flank. The volcanic
fumes reached a heightof 10 to 20 km, and ash
was carried eastward by
the prevailing westerly
winds, accumulating
several centimeters in thecity of Edo at the time,
which was about 100 km
away from the volcano.

Hoei Crater (photo by Shigeru Sudo)7

In areas where more than several tens of centimeters of volcanic ashfell, fields were completely wiped out, and the ash left behind caused
mudslides and floods whenever it rained, making life difficult for people
for several decades after the eruption.
Forty-nine days before the Hoei eruption, the Hoei Earthquake,
which is believed to have been triggered by a series of three earthquakes(Tokai, Tonankai, and Nankai) that occurred in conjunction, is said tohave triggered the eruption.
● Collapse and erosion of Mt. Fuji

Mt. Fuji has not always grown while erupting repeatedly. Fuji has
experienced a number of major and transformative collapses. The mostrecent collapse occurred on the eastern slope about 2,900 years ago.
The sediments from this event are called “Gotemba debris avalanche
sediments” and are thickly distributed over a wide area in Gotemba City.

Lake Yamanaka

Horei Crater
Pyroclastic
flow

Lava flow

Distribution of Gotemba debris avalanche deposits(National Research Institute for Earth Science and Disaster Prevention HP)

8This collapse is said to have been caused by an earthquake on the Fuji
River Estuary Fault Zone southwest of Mt. Fuji.
On Mt. Fuji, there are numerous radial valleys that are graduallyeroding the mountain body. On the western slope, there is a large erosion
valley that looks like a gaping wound. It is called the “Osawa Kuzure,”
and its width and depth extend up to 500 m and 150 m, respectively.
Downstream of the Osawa Kuzure, sediments accumulated due toerosion, creating a vast fan-shaped area.
N

Osawa Kuzure

S

Osawa Kuzure(National Institute of Land and Geography, 2003, with additional text)● Living Mt. Fuji

Mt. Fuji has repeatedly erupted and collapsed over the course of its
history and becomes present shape. A stratovolcano such as Mt. Fuji issaid to have a life span of several hundred thousand to one million years.
Mt. Fuji is a young volcano, only 100,000 years old, or about 10 years
old if compared to a human being.
Mt. Fuji has not erupted for about 300 years since the Hoei eruption,
but small earthquakes, believed to be caused by magma movement, haveoccurred 15 to 20 km underground. As mentioned in the introduction,
Mt. Fuji is an active volcano, and it is alive. For the life of a volcano,9300 years is just a moment, a fleeting sleep. We need to be prepared for
eruptions.

2. P REDICTION OF ERUPTION AND DISASTER
PREVENTION OF MT. FUJI
● Mt. Fuji Volcano Monitoring System

It is known that before a volcano erupts, magma rises fromunderground, causing the mountain to swell and earthquakes to occur.
Various systems are in place, including seismographs to monitor
earthquakes, tiltmeters, GPS, and strain gauges to monitor grounddeformation, air vibration gauges to monitor the sound waves that
accompany an eruption, and long-range cameras to capture volcanic
fumes.
Observation items
Seismogram
Inclinometer
GNSS
Strain meter
Total MagnetometerAir vibration meter
Remote camera

Mt. Fuji Volcano Observation System (Courtesy of JMA)

10

Mt. Fuji has not erupted for more than 300 years, and no eruption
has ever been monitored by instruments. Currently, the government anduniversities have placed more than 50 monitored instruments around Mt.
Fuji to predict eruptions, and the data is monitored (Kanshi) 24 hours a
day by the Japan Meteorological Agency (JMA).
● Various phenomena caused by the eruption of Mt. Fuji

Mt. Fuji has been called a “department store of eruptions” and has
caused various eruptions and disasters, ranging from small eruptions tolarge eruptions. The Japanese government is studying countermeasuresagainst pyroclastic flows, volcanic mudflows, lava flows, ash fall, andother eruptions that may occur at Mt. Fuji.

Volcanic Eruption Phenomena (Kagoshima Prefecture HP)● Eruption Alert Level of Mt. Fuji

When an eruption is about to start, the JMA sets eruption warninglevels to determine whether to prepare for evacuation or whether toevacuate. When the possibility of an eruption increases, the JMA issues
a warning and notifies the public through television and other media.
11Level 4 of the eruption warning
requires evacuation preparations andevacuation of the elderly and otherpersons requiring special care. Level
5 requires evacuation of dangerous
residential areas.
● Disaster Prevention Measuresat Mt. Fuji
Around Mt. Fuji, disaster prevention
measures are being promoted throughvarious instruments and facilities suchas weather observation stations, wire
sensors, and erosion control weirs to

Levels and Keywords
Level 5 Evacuation

Evacuation
Level 4 of the elderly,etc.
Mountain
Level 3 entry
restrictions
Restrictions
Level 2 and thecraterLevel 1

NormalVolcanic Alert Levels(Japan Meteorological Agency
Website)reduce disasters caused by eruptions, etc. When something unusual
happens, residents are notified through disaster prevention radio,
television, and radio.
● Impact of the Eruption of Mt. Fuji

If Mt. Fuji erupts, it will affect a wide area. If lava flows, up to
750,000 people in Yamanashi and Shizuoka prefectures are expected toevacuate.
“Hazard Map (Mt. Fuji Volcano Disaster Prevention Map)” hasbeen made to summarize possible future disasters. The map is based on
research into the history of past eruptions and summarizes areas where
the next disaster is likely to occur. The map includes a forecast of ash
fall caused by eruptions. If a major eruption were to occur at Mt. Fuji,
12ash fall is thought to affect areas as far away as Chiba Prefecture, morethan 100 km from Mt.Fuji. When we think of the effects of volcanic
eruptions, we tend to associate them with bright red lava flowing near
the mouth of an estuary. However, since volcanic ash does not melt likesnow, once it falls, it will have a significant impact on people’s lives fora long period of time over a wide area. For example, there is damage tovehicles, crops, and drinking water.
Assumed area of impact

Primary evacuation area
Secondary evacuation area

Third target area for evacuation
Area subject to evacuation Tier 4B

Area subject to evacuation Tier 4A

Fuji eruption (Crisis Management Department, Shizuoka Prefecture HP)

13

How to Extent of ash
More than 50cm
30-50cm
10-30cm
2-10cmMudflow reach area

Ash fall forecast map (Cabinet Office HP)

Damage to automobiles

Volcanic ash cleanup on road

3. BLESSINGS OF MT. FUJI
● A popular landscape from the past

Mt. Fuji is a beautiful conical shape that can be seen from any
direction, from east, west, south and north. This figure was also
featured as the subject of ukiyoe paintings from the late Edo period.
Representative ukiyoe include Katsushika Hokusai’s “Thirty-six Views
of Mount Fugaku” and Utagawa Hiroshige’s “Fifty-three Stages of the14Tokaido. Hokusai’s particularly famous ‘Red Fuji’ depicts Mount Fuji
on an early summer morning from the direction of Lake Kawaguchi. It
is a masterpiece that depicts the oxidized iron in the lava looks red on
the surface of Mt. Fuji in the morning sun.
In recent years, many resort facilities have been built to takeadvantage of the scenery around Mt. Fuji. When you visit these resort
facilities, think back to the time when Hokusai and Hiroshige lived.

53 Stations of the Tokaido Highway“Yuijuku” by Hiroshige Utagawa“Kappu Kasei” or “Red Fuji” by
Hokusai Katsushika● Abundant groundwater

There is usually no water flowing in the rivers on the mountainside of
Mt. Fuji. Since the ejecta of the new Fuji volcano, which is distributedon the surface of Mt Fuji, is extremely water permeable, rain andsnowmelt soak into the ground and flow toward the foot of the mountainas groundwater. For this reason, there are many springs around Mt. Fuji.
The famous spring on the north side of Mt. Fuji in Yamanashi Prefectureis the Oshinohakkai Spring. On the Shizuoka Prefecture side, the Kakita
River, Shiraito Falls, and the spring at Wakutama Pond are famous.
The figure on the right shows that most of these springs are locatednear the ends of the lava. For example, at Shiraito Falls, groundwater15

flows through the boundary
between the crumbly Shiraito
lava and less permeable layer
below, gushing out from thecliff at the end of the lava andcascading down like a cascading
thread.

Shiraito Falls (Fujinomiya City HP)

The Fuji Five Lakes“FujiG o k o ” o n t h e Ya m a n a s h iPrefecture side have no large
rivers flowing into them, but

Misaka Mountains

Lake kawaguchi
Lake Shoji Lake Sai

Lake Motosu

Oshino Hachikai(name of a
Buddhist priest)

they are always full of water.
to be that rain that falls on thenorthern foot of Mt. Fuji seeps
underground and gushes out at

Shogunate-owned land

The reason for this is thought

Yanzan region(inc. Aichi,
Nagano, Shizuoka,
Niigata, Toyama,
Ishikawa andFukui prefectures)the lower elevations of the Fuji

Lake Yamanaka
Mt Fuji
Shiraito Falls

Wellingtons pond

Mt Hakone

Mt Aitaka(in Kyoto)

Five Lakes.
Many mineral waters areproduced around Mt. Fuji.

Kakita River
Main spring

Mineral water is groundwater

Major springs around Mt.Fuji

that has flowed from lava andother sources from the New Fuji volcano. Most of the mineral water ispumped up from wells about 100 m deep. In terms of annual mineralwater production by prefecture in 2012, Yamanashi and Shizuoka
prefectures ranked first and second in the country, respectively. Bothprefectures are located around Mt. Fuji. This includes the amount of16

mineral water produced outside Mt. Fuji area, but these two prefectures
account for more than half of the national production.
Mineral water produced around Mt. Fuji contains more vanadium
than mineral water produced in other regions. This is because vanadiumis contained in high concentrations in the basaltic lava that erupts from
Mt. Fuji.
Kumamoto, 2%
Nagano, 2%
Gunma, 2%others9%

Toyama, 4%

Yamanashi
34%

Hokkaido, 4%Hyogo, 6%
Kagoshima, 6%
Tottori
10%

Shizuoka
21%

2012 Data

Comparison of Mineral Water Production by Prefecture(Created from the Japan Mineral Water Association website)● Hot springs to heal the soulCurrently, there are a number of hot spring facilities in various
locations around Mt. Fuji. However, the hot springs at these facilities
are not naturally gushing hot springs. They are dug in wells about 1,500
meters underground and pumped up to the surface in a temperature of 30
to 40 degrees Celsius. On the other hand, Hakone, near Mt. Fuji, is alsoa volcano, but it has hot springs that gush out naturally. Why do thesedifferences occur? Mt. Fuji is because the magma reservoirs that heat the
hot springs are located deep underground, making it more difficult for17the heat to be transmitted to the groundwater, while Hakone’s magma
reservoirs are located shallow.
Mt. Fuji is painted on the walls of many public bathhouses. It is
likely that people had a strong desire to soak in hot water while viewing
Mt. Fuji. These thoughts have been made a reality by digging wells
deep underground, and hot spring facilities have been built in various
locations at the foot of Mt. Fuji. Take a relaxing soak in a hot spring andenjoy the bounty of the earth.

Fuji on the wall of a public bathhouse. (Michikusa Society HP)

4. MT. FUJI TRIVIA● Temperature at the top of Mt. Fuji

Temperature of Mt. Fuji is observed at the Mt. Fuji Special Area
Weather Station located at the summit of Mt. Fuji. The average annual
temperature is -6.2 degrees Celsius. That of Asahikawa in Hokkaido
is 6.9 degrees Celsius, that of Tokyo is 16.3 degrees Celsius, and thatof Ishigaki Island in Okinawa Prefecture is 24.3 degrees Celsius.
18Thus, the temperature at the top of Mt Fuji is outstandingly low, andif you look for an area of this coldness on the plains, it corresponds tothe area around the Arctic Circle in Siberia. Mt. Fuji and the averagetemperatures in other parts of Japan, the differences can be clearly seen.
Duration of climbing Mt. Fuji is limited to about two months during thesummer season due to the severe weather conditions. When you climb
Mt. Fuji, please make sure you are fully equipped and safe.
point
January February March
Ishigaki Island 18.6
19.1
20.8
Tokyo
6.1
6.5
9.4
Asahikawa
-7.5
-6.5
-1.8
Mt. Fuji-18.4 -17.8 -14.2*単位（度）

April
23.3

May
25.7

June
28.0

July
29.5

August September October November December
29.2
27.9
25.9
23.2
20.1

yearly
24.3

16.3

14.6

18.9

22.1

25.8

27.4

23.8

18.5

13.3

8.7

5.6

11.8

16.5

20.2

21.1

15.9

9.2

1.9

-4.3

6.9

-8.7

-3.4

1.1

4.9

6.2

3.2

-2.8

-9.2

-15.1

-6.2

＊統計期間：1981～2010年

40
Ishigaki Island

Tokyo

Asahikawa

Mt. Fuji

Avg. Temperture ℃

30
20
10
0
Climing season

-10
-20
-30
y

ar

nu

Ja

ry

ua

br

Fe

ch

ar

M

ril

Ap

ay

M

ne

Ju

ly

Ju

r

st

gu

Au

be

m

te

p
Se

r

r

be

to

Oc

r

be

em

v
No

be

em

c
De

Temperatures in each area (plotted from JMA website)● Places where you can see Mt. Fuji

Mt. Fuji, the tallest mountain in Japan, can be seen from some places
far away and cannot be seen some places close by, due to the complex
topography of Japan. Fuji is visible from the northernmost point, Mt.
Hanazuka (elevation 919 m) on the border between Kawamata Town
19and Iitate Village in Fukushima Prefecture, which is 308 km away from
Mt. Fuji. The southern limit is Hachijo-jima Higashi-san (elevation 701m) in Hachijo Town, Tokyo, a distance of 271 km. The western limit isIrokawa Fujimi Toge in Nachikatsuura Town, Wakayama Prefecture, adistance of 323 km. It is not easy to see Mt. Fuji from those mountains
unless the weather conditions and other factors are right. Mt. Fuji isbecoming less and less visible from Tokyo due to buildings and otherfactors.
Mt Hiyama

Hachijojima
Higashi-san

Irokawa Fujimi
Toge▲：Top of Mt. Fuji

：Visible range of Mt.

Fuji (Sano, 2008, added)20

● Mt. Fuji in various locations

There are many mountains in Japanand around the world named “Mt.
Fuji.” The lowest mountain named Mt.
Fuji in Japan is Mt. Myoden Fuji in
Akita Prefecture. At 35 meters above
sea level, it is recognized by the Japan
Alpine Club as “the lowest Mt. Fuji inJapan. Yotei in Hokkaido is called “EzoFuji,” and Mount Kaimon in Kagoshima
Prefecture is called “Satsuma Fuji.”
Fuji is named after a mountain in
the world that resembles Mt.Fuji. For

Mt. Myoden Fuji (blog)
http://blog.goo.ne.jp/taic02/e/
bfc2a6b34e63aacca028aa170
baf44a2

example, Mount Osorno in south-central Chile is called “Chile Fuji,”
and Mount Taranaki on the west coast of New Zealand’s North Island iscalled “South Sea Fuji.”Mount Osorno(Sarah and Iain, 2007)

Mount Taranaki(Phillip Capper, 2008)21

● Banknotes and stamps

Mt. Fuji design is often used on banknotes. Old example is Mt. Fuji
on a 50 sen banknote issued in 1913. This banknote shows Mt Fuji fromMt Ashitaka. Mt. Fuji from Sasago-Kaigaharayama is shown on on theold 500-yen bill issued in 1951 and 1969. Mt. Fuji from the shores of
Lake Motosu is shown on the old 5,000-yen bill issued in 1984 and the
1,000-yen bill issued in 2004.
Mt. Fuji has been used on many postage stamps. The oldest known
examples are those issued in
the Taisho era (1912-1926).
Mt. Fuji is shown on the stamp
issued from Fuji Summit Post
Office. Mt. Fuji is also shown oncommemorative postage stamps
for Fuji Radar and the completionof the Tomei Expressway.

Fuji depicted on the 50 sen banknote(Eclipse2009, 2011)

Stamps with Mt. Fuji (blog)
Issued 1922, 8.00 on the left, 20.00
on the right
http://suzu22rann.web.fc2.com/
hujisann.html#hujisikakitte

It became the design of the old 5,000
yen bill.
Upside-down Fuji at Motosu-ko Lake
(Captain76, 2010)22

JAPAN GEOTECHNICAL CONSULTANTS ASSOCIATION
http://www.zenchiren.or.jp/
1-5-13,Uchikanda,Chiyoda-ku,Tokyo,101-0047,Japan
Tel:+81-3-3518-8873 FAX:+81-3-3518-8876

Front cover: New Year Fuji 4 January 2013 (Asia Air Survey Co., Ltd.)
Back cover: Tomei-Shin-Tomei Expressway and Mt Fuji (photo by
Yukito Yamashima)