Highway 304 is a national highway of

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

, leading from the

Bangkok Bangkok, officially known in Thai language, Thai as Krung Thep Maha Nakhon and colloquially as Krung Thep, is the capital and most populous city of Thailand. The city occupies in the Chao Phraya River delta in central Thailand and has an estima ...

suburb city of

Pak Kret Pak Kret ( th, ปากเกร็ด, ) is a city (''thesaban nakhon'') in Nonthaburi province, Thailand. It lies in the Central Thai plains on the east bank of the lower Chao Phraya River, bordering Bangkok to the east, Mueang Nonthaburi d ...

Nakhon Ratchasima Nakhon Ratchasima ( th, นครราชสีมา, ) is one of the four major cities of Isan, Thailand, known as the "big four of Isan". The city is commonly known as Korat (, ), a shortened form of its name. It is the governmental seat of ...

in the country's

Northeast The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

. It forms the main link between the

eastern Eastern may refer to: Transportation *China Eastern Airlines, a current Chinese airline based in Shanghai *Eastern Air, former name of Zambia Skyways *Eastern Air Lines, a defunct American airline that operated from 1926 to 1991 *Eastern Air Li ...

and northeastern regions, and is one of the major alternative routes into the Northeast (the main route from Bangkok being

Mittraphap Road Mittraphap Road (, , ) or Highway 2 (, ) is one of the four primary highways in Thailand, along with Phahonyothin Road (Highway 1), Sukhumvit Road (Highway 3), and Phetkasem Road (Highway 4). It runs from Saraburi to Nong Khai. The road was origi ...

, Highway 2). The highway is known by several names along its route. Chaeng Watthana Road ( th, ถนนแจ้งวัฒนะ) begins at Pak Kret in Nonthaburi Province, and leads eastward (and slightly south) to Lak Si Monument in Bangkok's Bang Khen District, where it crosses

Phahon Yothin Road Phahonyothin Road ( th, ถนนพหลโยธิน, , ) or Highway 1 is a main road in Bangkok and one of the four primary highways in Thailand, which include Mittraphap Road (Highway 2), Sukhumvit Road (Highway 3), and Phet Kasem Road ( ...

and from there becomes known as Ram Inthra Road (, also spelled Ramindra) until it reaches

Min Buri Min Buri ( th, มีนบุรี, ) is one of the 50 districts (''khet'') of Bangkok, Thailand. It is bounded by other Bangkok districts (from north clockwise): Khlong Sam Wa, Nong Chok, Lat Krabang, Saphan Sung, and Khan Na Yao. Min Buri ...

in Bangkok's eastern fringes. It then becomes known as Suwinthawong Road () towards the town of

Chachoengsao Chachoengsao ( th, ฉะเชิงเทรา, ) is a town (''thesaban mueang'') in central Thailand, capital of Chachoengsao Province. It is on the banks of the Bang Pakong River. It includes ''tambon'' Na Mueang and parts of Ban Mai, Bang T ...

. From there, it continues mostly northeastward through the eastern province of the same name, past the town of Phanom Sarakham, then enters

Prachin Buri Province Prachinburi province ( th, ปราจีนบุรี, , ) is one of Thailand's seventy-seven provinces (''changwat''), it lies in eastern Thailand. Neighboring provinces are (from north clockwise) Nakhon Ratchasima, Sa Kaeo, Chachoengsao, a ...

where it crosses Highway 33 at Kabin Buri town. It then leads north, crossing the Sankamphaeng Mountains through a pass between

Khao Yai Khao Yai National Park ( th, อุทยานแห่งชาติเขาใหญ่, , ) is a national park in Thailand. Established in 1962 as Thailand's first national park, it is the third largest national park in Thailand. Descr ...

and Thap Lan national parks into Nakhon Ratchasima Province. There, it passes through Wang Nam Khio and

Pak Thong Chai Pak Thong Chai (เทศบาลตำบลปักธงชัย), Pak Thong Chai District, Nakhon Ratchasima Province, effective 16 July 16, 2008. The TAO ''Tao'' or ''Dao'' is the natural order of the universe, whose character one's ...

districts before joining Mittraphap Road as it enters the city of Nakhon Ratchasima. Part of the highway is designated as

Asian Highway 19 Asian Highway 19 (AH19) is a road in the Asian Highway Network running 459 km from Nakhon Ratchasima to Bangkok in Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Sou ...

. The road was constructed in segments. The Chaeng Watthana and Suwinthawong sections were named in 1950, while the section from Chachoengsao to Nakhon Ratchasima (originally designated Highway 23) was built from 1941, and was initially unpaved. The Kabin Buri–Nakhon Ratchasima section was built and paved from 1965 to 1968 with assistance from the

United States Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...

to support the USAF bases in Thailand during the

Vietnam War The Vietnam War (also known by #Names, other names) was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vie ...

. The road, which cuts through the

Dong Phayayen–Khao Yai Forest Complex Dong Phayayen–Khao Yai Forest Complex is a UNESCO World Heritage Site in Thailand. It covers the areas of five protected areas in the Dong Phaya Yen Mountains and Sankamphaeng Range, namely Khao Yai National Park, Khao Yai, Thap Lan National Park ...

World Heritage Site, underwent expansion into a four-lane highway from 2015 to 2018, which included the construction of bridges and underpasses to serve as

wildlife corridor A wildlife corridor, habitat corridor, or green corridor is an area of habitat connecting wildlife populations separated by human activities or structures (such as roads, development, or logging). This allows an exchange of individuals between ...

s, the first in Thailand.

References

{{reflist National highways in Thailand