Greater Tokyo Area
From top: Skyscrapers in Shinjuku, and Surrounding of Ginza
Coordinates: 35°41′23″N 139°41′30″E / 35.68972°N 139.69167°E / 35.68972; 139.69167Coordinates: 35°41′23″N 139°41′30″E / 35.68972°N 139.69167°E / 35.68972; 139.69167
Country	Japan
Major Cities	Tokyo Metropolis (Included 23 special wards) Yokohama Kawasaki Sagamihara Saitama Chiba
Area
• Urban	3,925 km2 (1,515 sq mi)
• Metro	13,754 km2 (5,310 sq mi)
Population (Population Census of Japan 2000)[1]
• Urban	32,542,946
• Urban density	8,817/km2 (21,480/sq mi)
• Metro	34,607,069
• Metro density	2,516/km2 (6,516/sq mi)
GDP	2008 estimate
Nominal[2]	$1.941 trillion (¥165.01 trillion, The One Metropolis and Three Prefectures)
PPP	$1.479 trillion[3] (1st)

The Greater Tokyo Area is a large metropolitan area in Kantō region, Japan, consisting of most of the prefectures of Chiba, Kanagawa, Saitama, and Tokyo (at the center). In Japanese, it is referred to by various terms, including the National Capital Region (首都圏, Shuto-ken^?), One Metropolis, Three Prefectures (一都三県, Itto Sanken^?), and others.

A 2007 UN estimate puts the population at 35,676,000,^[4] making it by far the world's most populous metropolitan area. It covers an area of approximately 13,500 km² (5,200 mi²),^[5] giving it a population density of 2,642 person/km² - which is somewhat more than twice the population density of Bangladesh. It is the second largest single metropolitan area in the world in terms of built-up or urban function landmass at 7,800 km² (3,000 mi²).^[6] Only the New York metropolitan area, at 17,405 km², is larger.

The area has the largest metropolitan economy in the world, with a total GDP (nominal) of approximately US$1.9 trillion (¥165 trillion)^[2] in 2008. According to research published by PricewaterhouseCoopers, the agglomeration of Tokyo had a total GDP of US$1.479 trillion in 2008 (at purchasing power parity), ranking again as the largest urban agglomeration GDP in the world.^[3]

Definition[link]

There are various definitions of the Greater Tokyo Area. Each area has a different population figure and tries to incorporate different aspects.

Various definitions of Tokyo/Kantō[link]

Metropolitan area name	Details	Population	Area (km2)	Population Density (People/km2)	Agency	Pop Date	Map
Former area of Tokyo City Limit	23 special wards	8,949,447	621.9	14,390	Japan Statistics Bureau	2010 Census[7]
Tokyo Metropolis	Prefectural level jurisdiction (Tokyo-to) Prefectures of Japan excluding Izu/Ogasawara Islands	13,047,446	1808	7,216.5	Japan Statistics Bureau	2010 Census[7]
Tokyo Metropolitan Employment Area Tōkyō Dai-toshi Koyō-ken (東京大都市雇用圏?)	all municipalities that have at least 10% of their population commuting to 23 special wards Figures for this definition are complex to update without a major re-study.	31.7 million	-	-	Center for Spatial Information Service, the University of Tokyo	2000
One Metropolis, Three Prefectures (一都三県, Itto Sanken?)	Most Commonly Used Definition Misses many more distant suburbs that lay outside the prefectural borders, especially in Ibaraki and Gunma Incorporates sparsely settled rural districts like Nishitama and even islands like Minamitorishima, 1850 km away from central Tokyo	35,623,327	13,555.65	2,627.9	Japan Statistics Bureau	2010 Census[8]
Kantō Major Metropolitan Area (関東大都市圏, Kantō Dai-toshi-ken?)	One of the two definitions the Japan Statistics Bureau uses Consists of all municipalities that have at least 1.5% of their population aged 15 and above commuting to a designated city (Yokohama, Kawasaki, Sagamihara, Chiba, and Saitama) or the 23 special wards Before Saitama became a designated city in 2001, the area was called Keihin'yō Major Metropolitan Area (京浜葉大都市圏, Keihin'yō Dai-toshi-ken?) Most locally detailed definition, but hard to update without major re-study Excludes adjacent metropolitan areas of Gunma, Ibaraki, and Utsunomiya (ja:宇都宮都市圏) which are urbanized but have some small towns in between them and Tokyo.	35,682,460			Japan Statistics Bureau[9]	2005
Tokyo Major Metropolitan Area (東京大都市圏, Tōkyō Dai-toshi-ken?)	Set of municipalities that are completely or mostly within 50 and 70 kilometres of the Tokyo Metropolitan Government Buildings in Shinjuku Suburbs tend to extend in a finger like outward along major commuter train routes and density builds along express stops, not in a uniform fashion, so these definitions aren't the most accurate definition	31,505,458 (50 km), 35,097,758 (70 km)	-	-	Japan Statistics Bureau[10]	2005
Kantō region	Broad regional definition includes many rural areas	42,607,376	32,423.9	1,314.1	Japan Statistics Bureau	2010 Census[8]
National Capital Region	According to the National Capital Region Planning Act Includes many rural areas Essentially Kantō plus Yamanashi	43,470,148	36,889.28	1,178.4	Japan Statistics Bureau[10]	2010 Census[8]

International Comparison[link]

One Metropolis 3 Prefectures definition, the total size is smaller than Los Angeles County, and almost a third smaller at 13,555.65  km² than the Combined Statistical Area of New York, at 30,671 km². and 21.9 million people.

Metropolitan Area definition ambiguities and issues[link]

• The South Kantō region (南関東, Minami Kantō^?) is a potentially ambiguous term. Informally, it may mean the One Metropolis, Three Prefectures, or the area without Saitama Prefecture. Formally, it may mean the South Kantō Block, which is not the Greater Tokyo Area, but a proportional representation block of the national election, comprising Kanagawa, Chiba, and Yamanashi Prefectures.

• In informal occasions, the term National Capital Region (首都圏, Shuto-ken^?) often means Greater Tokyo Area. Officially, the term refers to a much larger area, namely the whole Kantō region and Yamanashi Prefecture.

• It should be noted that Tokyo as a metropolis includes some 394 km2
  of islands (Izu Islands and Ogasawara Islands), as well as some mountainous areas to the far west, which are not part of Greater Tokyo, but have comparatively very small population.

Cities[link]

(populations listed for those over 300,000)

Cities within Tokyo[link]

Tokyo is legally classified as a to (都^?), a word which translates as "metropolis," and is treated as one of the forty-seven prefectures of Japan. It is not administered as a single city.

Special wards of Tokyo

Shibuya

Eastern Tokyo Metropolis[link]

Central Tokyo, situated in the eastern portion of Tokyo Metropolis, was once incorporated as Tokyo City, which was dismantled during World War II. Its subdivisions have been reclassified as special wards (特別区, tokubetsu-ku^?). The twenty three special wards currently have the legal status of cities, with individual mayors and city councils, and call themselves "cities" in English. However, when listing Japan's largest cities, Tokyo's twenty three wards are often counted as one city. See: Special wards of Tokyo

Western Tokyo Metropolis[link]

Hachiōji

Western Tokyo, known as the Tama Area (Tama-chiiki 多摩地域) comprises a number of municipalities, including these suburban cities:

Cities outside Tokyo[link]

Chiba

Kawasaki

Saitama

Yokohama

Kawaguchi

The core cities of the Greater Tokyo Area outside Tokyo Metropolis are:

• Chiba (population 940,000)
• Kawasaki (population 1.36 million)
• Saitama (population 1.19 million)
• Yokohama (population 3.62 million)

The other cities in Chiba, Kanagawa and Saitama Prefectures are:

source: stat.go.jp census 2005

Additional cities[link]

In the major metropolitan area (MMA) definition used by the Japanese Statistics Bureau, the following cities in Ibaraki, Tochigi, Gunma, Yamanashi, and Shizuoka Prefectures are included:

Gunma Prefecture[link]

• Tatebayashi

Ibaraki Prefecture[link]

Shizuoka Prefecture[link]

• Atami

Tochigi Prefecture[link]

• Oyama

Yamanashi Prefecture[link]

• Ōtsuki
• Uenohara

Border areas[link]

Tighter definitions for Greater Tokyo do not include adjacent metropolitan areas of Numazu-Mishima (approx. 450,000) to the southwest, Maebashi-Takasaki-Ōta-Ashikaga (approx. 1,500,000 people) on the northwest, and Greater Utsunomiya (ja:宇都宮都市圏) approx. 1,000,000) to the north. If they are included, Greater Tokyo's population would be around 39 million.

Tokyo skyline from the northwest. The skyscrapers of Shinjuku lie 23 kilometers away on the other side of farms, parks, and suburbia. The trees in the foreground are the border of Tokyo and Saitama.

Geography[link]

Shinjuku

At the centre of the main urban area (approximately the first 10 km from Tokyo Station) are the 23 special wards, formerly treated as a single city but now governed as separate municipalities, and containing many major commercial centres such as Shinjuku, Shibuya, Ikebukuro and Ginza. Around the 23 special wards are a multitude of suburban cities which merge seamlessly into each other to form a continuous built up area, circumnavigated by the heavily-travelled Route 16 which forms a (broken) loop about 40 km from central Tokyo. Situated along the loop are the major cities of Yokohama (to the south of Tokyo), Hachiōji (to the west), Ōmiya (now part of Saitama City, to the north), and Chiba (to the east). Within the Route 16 loop, the coastline of Tokyo Bay is heavily industrialised, with the Keihin Industrial Area stretching from Tokyo down to Yokohama, and the Keiyō Industrial Zone from Tokyo eastwards to Chiba. Along the periphery of the main urban area are numerous new suburban housing developments such as the Tama New Town. The landscape is relatively flat compared to most of Japan, most of it comprising low hills.

Outside the Route 16 loop the landscape becomes more rural. To the southwest is an area known as Shōnan comprising various cities and towns along the coast of Sagami Bay, with their long beaches comprising black volcanic sand, and to the west the area is mountainous.

Many rivers run through the area, the major ones being Arakawa and Tama River.

Economy[link]

Tokyo has the largest city economy in the world and is one of three command centers along with New York City and London.

Greater Tokyo Area 2005[link]

Tokyo Metropolitan Government Building

• 2005 average exchange rate (1 US Dollar = 110.22 Yen)^[11]

Source ^[2]

GDP (purchasing power parity) 2005[link]

Tokyo Tower

The agglomeration of Tokyo is the world's largest economy, with the largest gross metropolitan product at purchasing power parity (PPP) in the world in 2005 according to a study by PricewaterhouseCoopers.^[12]

Rank	Urban agglomerations	Country	GDP(PPP) (in billion US$)
1	Tokyo	Japan	1,191
2	New York City	United States	1,133
3	Los Angeles	United States	639
4	Chicago	United States	460
5	Paris	France	460
6	London	United Kingdom	452
7	Osaka	Japan	341
8	Mexico City	Mexico	315
9	Philadelphia	United States	312
10	Washington, D.C.	United States	299

Transportation[link]

Narita International Airport

Yamanote Line, 3.61 million passengers ride per day

Shuto Expressway on Rainbow Bridge

Air[link]

The Greater Tokyo Area has two major airports, Tokyo International Airport, commonly known as Haneda Airport (chiefly domestic) and Narita International Airport (chiefly international). Minor facilities include the Chōfu and Honda Airport. Tokyo Heliport serves helicopter traffic, including police, fire, and news. Various military facilities handle air traffic: Naval Air Facility Atsugi (United States Navy and Japan Maritime Self-Defense Force), Hyakuri Airfield (Japan Air Self-Defense Force), Yokota Air Base (United States Air Force), and Camp Zama (United States Army). Hyakuri is being developed for civil aviation with plans for service to begin in March 2010; it will be called Ibaraki Airport.

Rail[link]

Greater Tokyo has an extensive railway network comprising high-speed rail, commuter rails, subways, monorails, private lines, trams and others. There are around 136 individual rail lines in the Greater Tokyo Area, and between 1,000 to 1,200 railway stations depending on one's definition of the area, most designed for heavy use, usually long enough to accommodate 10-car trains. Major stations are designed to accommodate hundreds of thousands of passengers at any given time, with miles of connecting tunnels linking vast department stores and corporate offices. Tokyo Station has underground connections that stretch well over 4 kilometers, and Shinjuku Station has well over 200 exits. Greater Tokyo's Railway Network is easily considered the world's largest in terms of both daily passenger throughput with a daily trips of over 40 million (20 million different passengers) as well as physical extent with approximately 2,578 kilometers of track. Some 57 percent of all Greater Tokyo residents used rail as their primary means of transport in 2001.^[13]

JR East and many other carriers crisscross the region with a network of rail lines. (See this map showing the Suica/PASMO accepting area that roughly corresponds with Greater Tokyo). The most important carriers include Keihin Kyūkō Electric Railway (Keikyū), Keisei Electric Railway, Keiō Electric Railway, Odakyū Electric Railway, Seibu Railway, Tōbu Railway, and Tōkyū Corporation. In addition to Tokyo's two subway systems — Tokyo Metro and Tokyo Metropolitan Bureau of Transportation (Toei and Toden lines), Yokohama operates three lines. The Tokyo Monorail provides service to Haneda Airport and other destinations.

Other[link]

The Shuto Expressway system connects other national expressways in the capital region.

Tokyo and Yokohama are major commercial seaports, and both the Maritime Self-Defense Force and United States Navy maintain naval bases at Yokosuka.

See also[link]

Tokyo portal

• List of metropolitan areas in Asia by population‎
• List of metropolitan areas in Japan by population
• National Capital Region (Japan) briefly shows the two definitions of the "Capital Area" (Shuto-ken.)

References[link]

External links[link]

• Urban Employment Areas in Japan (2000)

v t e Mass transit in the Greater Tokyo Area JR East lines (Tokyo urban/suburban area) ■ Akabane ■ Chūō ■ Rapid ■ Local ■ Hachikō ■ Itsukaichi ■ Jōban ■ Karasuyama ■ Kawagoe ■ Keihin-Tōhoku ■ Keiyō ■ Mito ■ Musashino ■ Nambu ■ Narita ■ Negishi ■ Nikkō ■ Ōme ■ Ryōmō ■ Sagami ■ Saikyō ■ ■ Shōnan-Shinjuku ■ Sōbu ■ Rapid ■ Local ■ Sotobō ■ Takasaki ■ Tōgane ■ Tōhoku Utsunomiya ■ Tōkaidō ■ Tsurumi ■ Uchibō ■ Yamanote ■ Yokohama ■ Yokosuka Tokyo Metro lines Chiyoda Fukutoshin Ginza Hibiya Marunouchi Namboku Tōzai Yūrakuchō Hanzōmon Toei subway lines Asakusa Ōedo Mita Shinjuku Major private lines Keikyu Keikyū Main Airport Daishi Kurihama Zushi Keiō Keiō Keiō New Dōbutsuen Inokashira Keibajō Sagamihara Takao Keisei Keisei Main Chiba Chihara Higashi-Narita Kanamachi Narita Sky Access Oshiage Odakyū Enoshima Odawara Tama Seibu Ikebukuro lines ■ Ikebukuro ■ Sayama ■ Seibu Chichibu ■ Seibu Yūrakucho ■ Toshima Shinjuku Lines ■ Shinjuku ■ Haijima ■ Kokubunji ■ Seibu-en ■ Tamagawa ■ Tamako Sōtetsu Sōtetsu Main Izumino Tōbu Tōbu main lines Daishi Isesaki Kameido Kinugawa Kiryū Koizumi Nikkō Noda Sano Utsunomiya Tōjō lines Tōjō Ogose Tōkyū ■ Den-en-toshi ■ Ikegami ■ Meguro ■ Ōimachi ■ Tōkyū Tamagawa ■ Tōyoko Other commuter rail lines Hokusō Kantō Jōsō Ryūgasaki Nagareyama Rinkai Saitama Rapid Shibayama Shin-Keisei Tōyō Rapid Tsukuba Express Minatomirai Kodomonokuni Minatomirai 21 Yokohama Municipal Subway Blue Green Other lines Monorails Chiba Monorail Disney Resort Shōnan Monorail Tama Monorail Tokyo Monorail People movers New Shuttle Seaside Nippori-Toneri Yamaguchi Yūkarigaoka Yurikamome Streetcars ■ Enoden ■ Setagaya ■ Toden Arakawa Cable cars and aerial tramways Ōyama Cable Car Hodosan Ropeway Takaotozan Railway Nokogiriyama Ropeway Mount Tsukuba Cable Car Mount Tsukuba Ropeway Akechidaira Ropeway Ikaho Ropeway Mitake Tozan Cable Car Fuji-Hakone-Izu subregion 3 cable 5 ropeways 5 rail lines Major terminals Rail Akihabara Chiba Ikebukuro Kawasaki Kita-Senju Ōmiya Ōtemachi Shibuya Shinagawa Shinjuku Tachikawa Tōkyō Ueno Yokohama Airports Haneda Int'l Narita Int'l Chofu Ibaraki Ports Yokohama Tokyo Miscellaneous Shinkansen PASMO Suica Transportation in Greater Tokyo Rail transport in Japan

Tokyo 東京
—  Metropolis  —
東京都 · Tokyo Metropolis
From top left: Nishi-Shinjuku, Tokyo Tower, Rainbow Bridge, Shibuya, National Diet Building
Seal Symbol
Anthem: Tokyo Metropolitan Song (東京都歌, Tokyo Toka?)[1]
Location of Tokyo in Japan
Satellite photo of Tokyo's 23 Special wards taken by NASA's Landsat 7
Tokyo Location of Tokyo in Japan
Coordinates: 35°41′22.22″N 139°41′30.12″E / 35.6895056°N 139.6917°E / 35.6895056; 139.6917Coordinates: 35°41′22.22″N 139°41′30.12″E / 35.6895056°N 139.6917°E / 35.6895056; 139.6917
Country	Japan
Region	Kantō
Island	Honshu
Divisions	23 special wards, 26 cities, 1 district, & 4 subprefectures
Government
• Type	Metropolis
• Governor	Shintaro Ishihara
• Capital	Shinjuku
Area(ranked 45th)
• Metropolis	2,187.66 km2 (844.66 sq mi)
• Metro	13,572 km2 (5,240 sq mi)
Population (August 1, 2011)[2][3]
• Metropolis	13,185,502
• Density	6,000/km2 (16,000/sq mi)
• Metro	35,682,460
• Metro density	2,629/km2 (6,810/sq mi)
• 23 Wards	8,967,665
	(2011 per Prefectural Government)
Demonym	Tokyoite
Time zone	Japan Standard Time (UTC+9)
ISO 3166-2	JP-13
Flower	Somei-Yoshino cherry blossom
Tree	Ginkgo tree (Ginkgo biloba)
Bird	Black-headed Gull (Larus ridibundus)
Website	www.metro.tokyo.jp

Tokyo (東京, Tōkyō^?, "Eastern Capital") [toːkʲoː], English /ˈtoʊki.oʊ/; officially Tokyo Metropolis (東京都, Tōkyō-to^?),^[4] is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of the world.^[5] It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family. Tokyo is in the Kantō region on the southeastern side of the main island Honshu and includes the Izu Islands and Ogasawara Islands.^[6] Tokyo Metropolis was formed in 1943 from the merger of the former Tokyo Prefecture (東京府, Tōkyō-fu^?) and the city of Tokyo (東京市, Tōkyō-shi^?).

The Tokyo Metropolitan government administers the 23 special wards of Tokyo (each governed as a city), which cover the area that was the city of Tokyo, as well as 39 municipalities in the western part of the prefecture and the two outlying island chains. The population of the special wards is over 8 million people, with the total population of the prefecture exceeding 13 million. The prefecture is part of the world's most populous metropolitan area with upwards of 35 million people and the world's largest urban agglomeration economy with a GDP of US$1.479 trillion at purchasing power parity in 2008, ahead of New York City metropolitan area, which ranks second on the list.^[7] The city hosts 47 of the Fortune Global 500 companies, the highest amount of any city.^[8]

Tokyo has been described as one of the three "command centers" for the world economy, along with New York City and London.^[9] The city is considered an alpha+ world city, listed by the GaWC's 2008 inventory^[10] and ranked fourth among global cities by A.T. Kearney's 2012 Global Cities Index.^[11] In 2010 Tokyo was named the second most expensive city for expatriate employees, according to the Mercer and Economist Intelligence Unit cost-of-living surveys,^[12] and in 2009 named the third Most Liveable City and the World’s Most Livable Megalopolis by the magazine Monocle.^[13] The Michelin Guide has awarded Tokyo by far the most Michelin stars of any city in the world.^[14][15] Tokyo hosted the 1964 Summer Olympics and is currently a Candidate City for the 2020 Summer Olympics.^[16]

Etymology[link]

Tokyo was originally known as Edo, which means "estuary".^[17] Its name was changed to Tokyo (Tōkyō: tō (east) + kyō (capital)) when it became the imperial capital in 1868, in line with the East Asian tradition of including the word capital ('京') in the name of the capital city.^[17] During the early Meiji period, the city was also called "Tōkei", an alternative pronunciation for the same Chinese characters representing "Tokyo". Some surviving official English documents use the spelling "Tokei".^[18] However, this pronunciation is now obsolete.^[19]

History[link]

Tokugawa Ieyasu

Tokyo was originally a small fishing village named Edo,^[6] in what was formerly part of the old Musashi Province.^[20]

Edo was first fortified by the Edo clan, in the late twelfth century. In 1457, Ōta Dōkan built Edo Castle. In 1590, Tokugawa Ieyasu made Edo his base and when he became shogun in 1603, the town became the center of his nationwide military government. During the subsequent Edo period, Edo grew into one of the largest cities in the world with a population topping one million by the 18th century.^[21] Tokyo became the de facto capital of Japan^[22] even while the emperor lived in Kyoto, the imperial capital. After about 263 years, the shogunate was overthrown under the banner of restoring imperial rule. In 1869, the 17-year-old Emperor Meiji moved to Edo. Tokyo was already the nation's political and cultural center,^[23] and the emperor's residence made it a de facto imperial capital as well, with the former Edo Castle becoming the Imperial Palace. The city of Tokyo was established, and continued to be the capital until it was abolished as a municipality in 1943 and merged with the "Metropolitan Prefecture" of Tokyo.

Central Tokyo, like Osaka, has been designed since about 1900 to be centered on major railway stations in a high-density fashion, so suburban railways were built relatively cheaply at street level and with their own right-of-way. This differs from many cities in the United States that are low-density and automobile-centric. Though expressways have been built in Tokyo, the basic design has not changed.

Tokyo went on to suffer two major catastrophes in the 20th century, but it recovered from both. One was the 1923 Great Kantō earthquake, which left 140,000 dead or missing,^[24] and the other was World War II. The Bombing of Tokyo in 1944 and 1945, with 75,000 to 200,000 killed and half of the city destroyed, was almost as devastating as the atomic bombs of Hiroshima and Nagasaki combined.^[25]

After the war, Tokyo was completely rebuilt, and was showcased to the world during the 1964 Summer Olympics. The 1970s brought new high-rise developments such as Sunshine 60, a new and controversial^[26] airport at Narita in 1978 (some distance outside city limits), and a population increase to about 11 million (in the metropolitan area).

Tokyo's subway and commuter rail network became one of the busiest in the world^[27] as more and more people moved to the area. In the 1980s, real estate prices skyrocketed during a real estate and debt bubble. The bubble burst in the early 1990s, and many companies, banks, and individuals were caught with mortgage backed debts while real estate was shrinking in value. A major recession followed, making the 1990s Japan's "Lost Decade"^[28] from which it is now slowly recovering.

Tokyo still sees new urban developments on large lots of less profitable land. Recent projects include Ebisu Garden Place, Tennozu Isle, Shiodome, Roppongi Hills, Shinagawa (now also a Shinkansen station), and the Marunouchi side of Tokyo Station. Buildings of significance are demolished for more up-to-date shopping facilities such as Omotesando Hills.

Land reclamation projects in Tokyo have also been going on for centuries. The most prominent is the Odaiba area, now a major shopping and entertainment center. Various plans have been proposed^[29] for transferring national government functions from Tokyo to secondary capitals in other regions of Japan, in order to slow down rapid development in Tokyo and revitalize economically lagging areas of the country. These plans have been controversial^[30] within Japan and have yet to be realized.

The 2011 Tōhoku earthquake and tsunami that devastated much of the northeastern coast of Honshu was felt in Tokyo. However, due to Tokyo's earthquake-resistant infrastructure, damage in Tokyo was very minor compared to areas directly hit by the tsunami,^[31] although activity in the city was largely halted.^[32] The subsequent nuclear crisis caused by the tsunami has also largely unaffected Tokyo, despite occasional spikes in radiation levels.^[33][34]

Geography and administrative divisions[link]

The mainland portion of Tokyo lies northwest of Tokyo Bay and measures about 90 km east to west and 25 km north to south. The average elevation in Tokyo is 40 m (131 ft 3 in).^[35] Chiba Prefecture borders it to the east, Yamanashi to the west, Kanagawa to the south, and Saitama to the north. Mainland Tokyo is further subdivided into the special wards (occupying the eastern half) and the Tama area (多摩地域) stretching westwards.

Tokyo Metropolitan Government Building

Also within the administrative boundaries of Tokyo Metropolis are two island chains in the Pacific Ocean directly south: the Izu Islands, and the Ogasawara Islands, which stretch more than 1,000 km away from the mainland. Because of these islands and mountainous regions to the west, Tokyo's overall population density figures far underrepresent the real figures for urban and suburban regions of Tokyo.

Under Japanese law, Tokyo is designated as a to (都), translated as metropolis.^[36] Its administrative structure is similar to that of Japan's other prefectures. Within Tokyo lie dozens of smaller entities, including many cities, the 23 special wards, districts, towns, villages, a quasi-national park, and a national park. The 23 special wards (特別区 -ku), which until 1943 constituted the city of Tokyo, are now separate, self-governing municipalities, each having a mayor, a council, and the status of a city.