is a national highway of

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 north ...

connecting

Kita-ku, Osaka is one of 24 wards of Osaka in Japan. Incidents and accidents 2021 Osaka building fire Notable locations Kita-ku, particularly the Umeda area surrounding Osaka Station, is one of the main commercial centers of Osaka. Kita-ku is also a fina ...

and

Kameoka, Kyoto is a city in Kyoto Prefecture, Japan. , the city had an estimated population of 87,518 in 29,676 households and a population density of 390 persons per km². The total area of the city is . Geography Kameoka abuts Kyoto to the east and is loca ...

in the

Kansai region The or the , lies in the southern-central region of Japan's main island Honshū. The region includes the prefectures of Nara, Wakayama, Kyoto, Osaka, Hyōgo and Shiga, often also Mie, sometimes Fukui, Tokushima and Tottori. The metropolita ...

of Japan.

Route description

National Route 423 has a total length of .

Minō Toll Road

The Minō Toll Road is a two-lane toll road in

Minoh, Osaka is a city in northwestern Osaka Prefecture, Japan. Its name is commonly romanized as "Minō" or "Minoo"; however, the city government officially uses the spelling Minoh in English. As of October 2016, the city has an estimated population of 134 ...

that connects the

Shin-Meishin Expressway The or simply ''Shin-Meishin'' for short is an expressway, linking Mie prefecture to Hyōgo Prefecture, which is partially open and partially under construction. The expressways current length as of February 2008 is 49.7 km. It connects to ...

to the southern limits of the city via a tunnel under Mount Minō. It is a part of Route 423 that is tolled and maintained by the Osaka Prefectural Road Corporation.

Shinmidō-suji

Shinmidosuji, Osaka (Flickr id 374463010)

Shin-Yodogawa-Ohashi Bridge, Osaka (04) IMG 2026-2 20130407

The Shinmidō-suji is a

controlled-access highway A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...

that runs from the northern terminus of the

Midōsuji Avenue is the primary main street in central Osaka, Japan. It runs north-south, passing Umeda, Nakanoshima, Shinsaibashi, Dōtonbori, Ame-mura, and Namba districts. Underneath the street is the Midōsuji Line subway. Especially in autumn when ...

in Kita-ku to the southern terminus of the Minō Toll Road in Minoh. From Kita-ku to

Toyonaka is a city in Osaka Prefecture, Japan. The city was founded on October 15, 1936. Geography Climate Toyonaka has a Humid subtropical climate (Köppen ''Cfa'') characterized by warm summers and cool winters with light to no snowfall. The averag ...

, the

median In statistics and probability theory, the median is the value separating the higher half from the lower half of a data sample, a population, or a probability distribution. For a data set, it may be thought of as "the middle" value. The basic fe ...

of the highway is utilized by the

Midōsuji Line The is a rapid transit line in Osaka, Japan, operated by Osaka Metro. Constructed under Midōsuji, a major north-south street, it is the oldest line in the Osaka subway system and the second oldest in Japan, following the Tokyo Metro Ginza Lin ...

and

Kita-Osaka Kyuko Railway is a railway operator in Osaka Prefecture, Japan. Its sole line, officially named the , operates as an extension of the Midōsuji Line of the Osaka Metro. The , established on 11 December 1967, is majorly owned by Hankyu. ''Kitakyu'', as it is ...

History

Much of what is now National Route 423 was part of the Settan-kaido, a road linking Ikeda in what was

Settsu Province was a province of Japan, which today comprises the southeastern part of Hyōgo Prefecture and the northern part of Osaka Prefecture. It was also referred to as or . Osaka and Osaka Castle were the main center of the province. Most of Settsu's ...

and Kameoka in what was then

Tanba Province was a province of Japan in the area of central Kyoto and east-central Hyōgo Prefectures. Tanba bordered on Harima, Ōmi, Settsu, Tajima, Wakasa, and Yamashiro Provinces. Its abbreviated form name was . In terms of the Gokishichidō system ...

. In 1964, the portion of the route between Kita-ku and Osaka Prefecture Route 9, known as the Shinmidō-suji, was built alongside the extended

to accommodate automobile traffic from

Shin-Ōsaka Station is a railway station in Yodogawa-ku, Osaka, Japan. It is the western terminus of the high-speed Tōkaidō Shinkansen line from Tokyo, the eastern terminus of the San'yō Shinkansen and one of Osaka's main railway terminals to the north. The lines ...

into central Osaka. Later in the decade, Shinmidō-suji was extended north again along with the Midōsuji Line to

Suita is a city located in northern Osaka Prefecture, Japan. As of October 1, 2016, the city has an estimated population of 378,322 and a population density of 9,880 persons per km². The total area is 36.11 km². The city was founded on April 1, ...

were the venue for the

Expo '70 The or Expo 70 was a world's fair held in Suita, Osaka Prefecture, Japan between March 15 and September 13, 1970. Its theme was "Progress and Harmony for Mankind." In Japanese, Expo '70 is often referred to as . It was the first world's fair ...

was. National Route 423 was established in 1982 along the Shinmidō-suji, the planned Minō Toll Road, and the older Settan-kaido. The Minō Toll Road section was opened to traffic on 30 May 2007 between Osaka Route 9 and the northern terminus at the Ikeda–Minoh route of National Route 423, completing the route. On 10 December 2017 the highway was connected to the Shin-Meishin Expressway at the northern terminus of the Ikeda–Minoh route and the toll road.

List of major junctions

Ikeda–Minoh route

The entire toll road is in

Osaka Prefecture is a Prefectures of Japan, prefecture of Japan located in the Kansai region of Honshu. Osaka Prefecture has a population of 8,778,035 () and has a geographic area of . Osaka Prefecture borders Hyōgo Prefecture to the northwest, Kyoto Prefecture ...

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