is a

national highway National highway or National Highway may refer to: * National Highways (England) * National Highway (Australia) * List of National Roads in Belgium * Brunei National Roads System * National Highway System (Canada) * Trans ...

connecting

Tokyo Tokyo (; ja, 東京, , ), officially the Tokyo Metropolis ( ja, 東京都, label=none, ), is the capital and largest city of Japan. Formerly known as Edo, its metropolitan area () is the most populous in the world, with an estimated 37.46 ...

and Shiojiri,

Nagano prefecture is a landlocked prefecture of Japan located in the Chūbu region of Honshū. Nagano Prefecture has a population of 2,052,493 () and has a geographic area of . Nagano Prefecture borders Niigata Prefecture to the north, Gunma Prefecture to the ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

. Originating at

Nihonbashi is a business district of Chūō, Tokyo, Japan which grew up around the bridge of the same name which has linked two sides of the Nihonbashi River at this site since the 17th century. The first wooden bridge was completed in 1603. The curre ...

Chūō, Tokyo is a special ward that forms part of the heart of Tokyo, Japan. The ward refers to itself in English as Chūō City. It was formed in 1947 as a merger of Kyobashi and Nihonbashi wards following Tokyo City's transformation into Tokyo Metrop ...

, it passes through

Shinjuku is a special ward in Tokyo, Japan. It is a major commercial and administrative centre, housing the northern half of the busiest railway station in the world ( Shinjuku Station) and the Tokyo Metropolitan Government Building, the administration ...

and four other wards, and then seven cities, including Hachiōji in Tokyo. It follows a westward route into

Kanagawa Prefecture is a prefecture of Japan located in the Kantō region of Honshu. Kanagawa Prefecture is the second-most populous prefecture of Japan at 9,221,129 (1 April 2022) and third-densest at . Its geographic area of makes it fifth-smallest. Kanag ...

, passing through the city of

Sagamihara is a city in Kanagawa Prefecture, Japan. , the city has an estimated population of 723,470, with 334,812 households, and a population density of 1,220 persons per km2. The total area of the city is . Sagamihara is the third-most-populous city ...

and one town. Continuing into

Yamanashi Prefecture is a prefecture of Japan located in the Chūbu region of Honshu. Yamanashi Prefecture has a population of 817,192 (1 January 2019) and has a geographic area of 4,465 km2 (1,724 sq mi). Yamanashi Prefecture borders Saitama Prefecture to the ...

, the highway passes through nine cities and towns, among them the prefectural capital of Kofu. In Nagano Prefecture, National Route 20 passes through five cities and towns before entering Shiojiri, where it terminates at the intersection of National Routes 19 and 153. The highway is 225.0 km long. National Route 20 is the successor to the

Kōshū Kaidō The was one of the five routes of the Edo period. It was built to connect Edo (modern-day Tokyo) with Kai Province in modern-day Yamanashi Prefecture, Japan. The route continues from there to connect with the Nakasendō's Shimosuwa-shuku in ...

, an

Edo period The or is the period between 1603 and 1867 in the history of Japan, when Japan was under the rule of the Tokugawa shogunate and the country's 300 regional '' daimyo''. Emerging from the chaos of the Sengoku period, the Edo period was character ...

highway connecting the shogunal capital of

Edo Edo ( ja, , , "bay-entrance" or "estuary"), also romanized as Jedo, Yedo or Yeddo, is the former name of Tokyo. Edo, formerly a ''jōkamachi'' (castle town) centered on Edo Castle located in Musashi Province, became the ''de facto'' capital of ...

and Kofu, then the principal city in Kai Province (or Kōshū, as it was also known). Parts of it still bear the old name. The highway's course passes the Sakurada Gate of the

Tokyo Imperial Palace The is the main residence of the Emperor of Japan. It is a large park-like area located in the Chiyoda district of the Chiyoda ward of Tokyo and contains several buildings including the where the Emperor has his living quarters, the where va ...

Shinjuku Station is a major railway station in the Shinjuku and Shibuya wards in Tokyo, Japan. In Shinjuku, it is part of the Nishi-Shinjuku and Shinjuku districts. In Shibuya, it is located in the Yoyogi and Sendagaya districts. It is the world's busiest ...

is on National Route 20. The

marathon The marathon is a long-distance foot race with a distance of , usually run as a road race, but the distance can be covered on trail routes. The marathon can be completed by running or with a run/walk strategy. There are also wheelchair div ...

course of the Tokyo Olympics included parts of National Route 20.

History

*4 December 1952 - First Class National Highway 20 (from

Shiojiri, Nagano is a city located in Nagano Prefecture, Japan. , the city had an estimated population of 67,240 in 27,602 households, and a population density of 230 persons per km². The total area of the city is . Geography Shiojiri is located in central N ...

) *1 April 1965 - General National Highway 20 (from

)

Overlapping sections

*From Nihonbashi to Chiyoda (Sakuradamon intersection):

Route 1 The following highways are numbered 1. For roads numbered A1, see list of A1 roads. For roads numbered B1, see list of B1 roads. For roads numbered M1, see List of M1 roads. For roads numbered N1, see list of N1 roads. For roads number ...

*In Hachioji, from Yokamachi intersection to Hachimancho intersection: Route 16 *In Otsuki, from intersection to Otsuki-bashi east intersection: Route 139 *From Kai (Ryuo-rittai intersection) to Nirasaki (Funayama-bashi kita intersection):

Route 52 The following highways are numbered 52: Australia * Kings Highway (Australia) * Isis Highway ( Childers to Ban Ban Springs) - Queensland State Route 52 (Wide Bay–Burnett Region) * Gillies Highway - Queensland State Route 52 (Far North Queensl ...

Intersects with

**Routes 4 and 15; at the origin, in Nihonbashi (Route 4 overlaps with 6, 14 and 17) **

; from Nihonbashi to Chiyoda ** Route 246; at Chiyoda ** Chofu IC, Chuo Expressway at Chōfu ** Kunitachi-Fuchu IC, Chuo Expressway at Kunitachi ** Route 16; at Hachioji *

** Route 412 and Sagamiko-Higashi Exit, Chuo Expressway; at Sagamihara ** Sagamiko IC, Chuo Expressway at Sagamihara *

** Route 139 and Otsuki IC, Chuo Expressway; at Otsuki ** Route 137; at Fuefuki **Routes 140 and

358 Year 358 ( CCCLVIII) was a common year starting on Thursday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Datianus and Cerealis (or, less frequently, year 1111 ''Ab urb ...

; at Kofu **

; from Kai to Nirasaki ** Route 141; at Nirasaki *

Nagano Prefecture is a landlocked prefecture of Japan located in the Chūbu region of Honshū. Nagano Prefecture has a population of 2,052,493 () and has a geographic area of . Nagano Prefecture borders Niigata Prefecture to the north, Gunma Prefecture to the ...

**Routes 152 and

299 __NOTOC__ Year 299 ( CCXCIX) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar. In the Roman Empire, it was known as the Year of the Consulship of Diocletian and Maximian (or, less frequently, ...

; at Chino ** Route 142; at Shimosuwa **Routes 19 and 153; at the terminus, in Shiojiri

References

{{National Routes of Japan, 20 020 Roads in Kanagawa Prefecture Roads in Nagano Prefecture Roads in Tokyo Roads in Yamanashi Prefecture