Existed: 1950 – present Length 1,274 km | Constructed 1950 | |
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Phet Kasem Road (Thai: ถนนเพชรเกษม, rtgs: thanon phet kasem) or Thailand Route 4 (Thai: ทางหลวงแผ่นดินหมายเลข 4, ) is one of the four major highways in Thailand, along with Phahonyothin Road (Route 1), Mittraphap Road (Route 2), and Sukhumvit Road (Route 3). At 1,274 km, it is the longest highway in Thailand. It begins at Naowa Chamnian bridge in Bangkok Yai, Bangkok. It is named after Luang Phet Kasemwithisawasdi, the seventh director general of the Department of Highways.
Map of Thanon Phetkasem, Thailand
The provinces along the road are Samut Sakhon, Nakhon Pathom, Ratchaburi, Phetchaburi, Prachuap Khiri Khan, Chumphon, Ranong, Phangnga, Krabi, Trang, Phatthalung and Songkhla, linked to North-South Expressway (NSE) of Malaysia at Sadao pass and Bukit Kayu Hitam pass.
Three sections of the highway are also the Asian Highway AH2.