Phetkasem Road or Thailand Route 4 is one of the four major highway

Highway

A highway is any public road. In American English, the term is common and almost always designates major roads. In British English, the term designates any road open to the public. Any interconnected set of highways can be variously referred to as a "highway system", a "highway network", or a...

s in Thailand

Thailand

Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...

, along with Phahonyothin Road (Route 1), Mittraphap Road (Route 2), and Sukhumvit Road

Sukhumvit Road

Sukhumvit Road , or Thailand Route 3 , is a major road in Thailand, and a major surface road of Bangkok and other cities it winds through. It follows a coastal route from Bangkok to Trat and is just over in length....

 (Route 3). At 1,274 km, it is the longest highway in Thailand. It begins at Naowa Chamnian bridge in Bangkok Yai

Bangkok Yai

Bangkok Yai is one of the 50 districts of Bangkok, Thailand. Neighboring districts are Bangkok Noi, Phra Nakhon , Thon Buri, Phasi Charoen, and Taling Chan.-History:...

, Bangkok

Bangkok

Bangkok is the capital and largest urban area city in Thailand. It is known in Thai as Krung Thep Maha Nakhon or simply Krung Thep , meaning "city of angels." The full name of Bangkok is Krung Thep Mahanakhon Amon Rattanakosin Mahintharayutthaya Mahadilok Phop Noppharat Ratchathani Burirom...

. It is named after Luang Phetkasemwithisawasdi, the seventh director general of the Department of Highways.

The provinces along the road are Samut Sakhon

Samut Sakhon Province

Samut Sakhon ) is one of the central provinces of Thailand.Neighboring provinces are Samut Songkhram, Ratchaburi, Nakhon Pathom and Bangkok.- Etymology :...

, Nakhon Pathom

Nakhon Pathom Province

Nakhon Pathom ) is one of the central provinces of Thailand. Neighboring provinces are Suphan Buri, Ayutthaya, Nonthaburi, Bangkok, Samut Sakhon, Ratchaburi and Kanchanaburi...

, Ratchaburi

Ratchaburi Province

Ratchaburi is one of the central provinces of Thailand. Neighboring provinces are Kanchanaburi, Nakhon Pathom,Samut Sakhon, Samut Songkhram and Phetchaburi...

, Phetchaburi

Phetchaburi Province

Phetchaburi is one of the central provinces of Thailand. Neighboring provinces are Ratchaburi, Samut Songkhram and Prachuap Khiri Khan...

, Prachuap Khiri Khan

Prachuap Khiri Khan Province

Prachuap Khiri Khan is one of the central provinces of Thailand. Neighboring provinces are Phetchaburi in the north and Chumphon in the south. To the west it borders Tanintharyi Division of Myanmar....

, Chumphon

Chumphon Province

Chumphon ) is one of the southern provinces of Thailand, at the shore of the Gulf of Thailand. Neighboring provinces are Prachuap Khiri Khan, Surat Thani and Ranong...

, Ranong

Ranong Province

Ranong is one of the southern provinces of Thailand, on the coast of the Andaman Sea. It is the province with the fewest citizens. Neighboring provinces are Chumphon, Surat Thani and Phang Nga...

, Phang Nga

Phang Nga Province

Phang Nga is one of the southern provinces of Thailand, on the shore to the Andaman Sea. Neighboring provinces are Ranong, Surat Thani and Krabi. To the south is the Phuket province, but without land boundary to Phang Nga....

, Krabi

Krabi Province

Krabi is one of the southern provinces of Thailand, at the shore of the Andaman Sea. Neighbouring provinces are Phang Nga, Surat Thani, Nakhon Si Thammarat and Trang. The Phuket province to the west is also neighbouring, but without any land boundary...

, Trang

Trang Province

Trang is one of the southern provinces of Thailand, at the western shore of the Malay Peninsula to the Andaman Sea. Neighboring provinces are Krabi, Nakhon Si Thammarat, Phatthalung and Satun....

, Phattalung and Songkhla

Songkhla Province

Songkhla is one of the southern provinces of Thailand. Neighboring provinces are Satun, Phatthalung, Nakhon Si Thammarat, Pattani and Yala. To the south it borders Kedah and Perlis of Malaysia....

, linked to North-South Expressway (NSE) of Malaysia at Sadao

Sadao

-Places:* Sadao, Sadao - Sadao District - Songkhla Province, Southern Thailand* Sadao, Buachet - Buachet District - Surin Province North-Eastern Thailand* Sadao, Nang Rong - Nang Rong District - Buriram Province North-Eastern Thailand...

 pass and Bukit Kayu Hitam

Bukit Kayu Hitam

Bukit Kayu Hitam is Kedah's main border town on the Malaysia-Thailand Border. It marks the end of the North-South Expressway and Malaysia Federal Route 1, the longest Malaysian road which runs from Johor Bahru, Johor in the south till the border at Bukit Kayu Hitam pass. The checkpoint and duty...

 pass.

Three sections of the highway are also the Asian Highway AH2

AH2

The AH2 is a road in the Asian Highway Network running 8230 miles from Denpasar, Indonesia to Khosravi, Iran. The route is as follows:-Indonesia:Denpasar — Surabaya — Surakarta — Semarang — Cikampek — Jakarta...

.

• From Nakhon Pathom
  Nakhon Pathom Province
  Nakhon Pathom ) is one of the central provinces of Thailand. Neighboring provinces are Suphan Buri, Ayutthaya, Nonthaburi, Bangkok, Samut Sakhon, Ratchaburi and Kanchanaburi...
  
   to Chumphon
  Chumphon Province
  Chumphon ) is one of the southern provinces of Thailand, at the shore of the Gulf of Thailand. Neighboring provinces are Prachuap Khiri Khan, Surat Thani and Ranong...
  
  
• From Phattalung to Ban Khu Ha
• From Hat Yai
  Hat Yai
  Hat Yai is a city in southern Thailand near the Malaysian border. Located at , it has a population of 157,359 in the city itself and about 800,000 in the greater Hat Yai area. Hat Yai is the largest city of Songkhla Province, the largest metropolitan area in Southern, and third largest...
  
   to Malaysia border, where it connects to the North-South Expressway, Malaysia