
LANDSCAPE AND
ENVIRONMENT
Japan is an archipelago in the Pacific Ocean along
the eastern coast of the Asian mainland. The archi-
pelago includes four main islands—Honshu, Hok-
kaido, Kyushu, and Shikoku in descending order of
size—and more than 1,000 other islands of varying
sizes. The total area of Japan is approximately
145,885 square miles, slightly smaller than the state
of California. The four main islands are some 1,200
miles in length (northeast to southwest) with a width
of about 200 miles at the widest point. These four
islands comprise approximately 95 percent of Japan’s
entire landmass.
The Japanese islands are situated at the intersec-
tion of four tectonic plates. The collision of these
plates is the source of the many earthquakes, volca-
noes, hot springs, and other geological phenomena
that have occurred frequently throughout Japanese
history. As a result of this geologic instability, moun-
tains cover some 80 percent of the Japanese land-
scape. Historically, this mountainous land surface
resulted in the division of Japan into regions set into
plains between mountain ranges. Of particular im-
portance during the medieval and early modern
periods are the Kanto Plain—the site of the cities of
Edo and Kamakura—and the Kansai Plain in which
Kyoto and Osaka are situated.
Oceans, Bays, Lakes,
and Rivers
Japan is completely surrounded by water. Thus, rel-
ative to other East Asian nations, Japan exists in geo-
graphical isolation, a feature that has allowed it to
draw upon Chinese, Korean, and other continental
influences when it chose to do so, and to isolate itself
from outside influences at other times. The Sea of
Japan separates Japan from China (500 miles at the
closest point) and Korea (120 miles at the closest
point). The Seto Inland Sea (Seto Naikai), a part of
the Pacific Ocean, creates sea boundaries between
Honshu, Shikoku, and Kyushu. Some 1,000 islands
populate the Seto Inland Sea. This sea and its islands
were significant to trade and transportation during
the medieval and early modern periods. Other ocean
boundaries between the four main islands include
several straits (kaikyo), such as the Kammon Strait
(also called Shimonoseki Strait; located between
Honshu and Kyushu), the Tsugaru Strait (situated
between Honshu and Hokkaido), the Naruto Strait
(at the entry to Osaka Bay), and the Tsushima Strait
(between Iki Island and Tsushima Island in the
Pacific Ocean).
During the medieval and early modern periods,
several bays (wan) served as calm waters for ports
that conducted both domestic and foreign trade.
Among the more significant in this time period were
Osaka Bay, Edo Bay (present-day Tokyo Bay), Ise
Bay, and Uraga Bay.
There are few lakes on the Japanese islands,
though Lake Biwa (Biwako) in central Honshu, Ja-
pan’s largest freshwater lake, is a notable exception.
Lake Biwa (area: 259 square miles; circumference:
172 miles) was fished and used for transportation in
the medieval and early modern periods. Lake Biwa
also secured a place in the Japanese imagination for
its Eight Views of Omi. This refers to eight loca-
tions around Lake Biwa in Omi Province (present-
day Shiga Prefecture) that were praised for their
beauty from at least the beginning of the 16th cen-
tury and were a subject for Edo-period artists.
The Japanese landscape is marked by many
rivers, but most of them are rather short. Only two
rivers, the Shinanogawa and the Tonegawa on Hon-
shu, exceed a length of 200 miles. Historically, rivers
were used mostly for crop irrigation rather than ship
navigation. Flooding also impacted medieval and
early modern life. Some important rivers include:
Ara River (Arakawa; length: 105 miles) Originates
in the Kanto Mountain, ends in Edo Bay (present-
day Tokyo Bay)
Chikugo River (Chikugogawa; length: 89 miles)
Longest river in Kyushu
Edo River (Edogawa; length: 37 miles) Flows into
Edo Bay (Tokyo Bay)
H ANDBOOK TO L IFE IN M EDIEVAL AND E ARLY M ODERN J APAN
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