Mittraphap Road (Thai: ถนนมิตรภาพ, RTGSthanon mittraphap, pronounced [tʰā.nǒn mít.trā.pʰâːp]) or Thailand Route 2 (Thai: ทางหลวงแผ่นดินหมายเลข 2, RTGSThang Luang Phaendin Mailek Song) is one of the four major highways in Thailand, along with Phahonyothin Road (Route 1), Sukhumvit Road (Route 3), and Phetkasem Road (Route 4). It runs from Saraburi to Nong Khai.

Thailand Route 2 shield}}

Thailand Route 2
ทางหลวงแผ่นดินหมายเลข 2
ถนนมิตรภาพ Thanon Mittraphap
"Friendship Highway"
Thanon Mittraphap.png
Route information
Part of
Length509.113 km (316.348 mi)
Major junctions
Southwest endSaraburi, Thai Highway-1.svg Phahonyothin Rd.
Northeast endNong Khai, Thai–Lao Friendship Bridge
ProvincesSaraburi, Nakhon Ratchasima
Khon Kaen
Udon Thani, Nong Khai
Highway system
Highways in Thailand

The road was originally built from Khorat to Nong Khai by the United States in 1955–1957[1] at a cost of US$20 million to supply its northeastern military bases.[2]:56-57

It is the first highway in Thailand to meet international standards, and the first highway in Thailand to use both asphalt and concrete. It received the name "Thanon Mittraphap" on 20 February 1957. The name literally means "Friendship Road". It is the main road that connects Isan (northeastern Thailand) across the Dong Phaya Yen Range. The highway begins at Saraburi, Phahonyothin Road (Route 1) junction. It passes through the provinces of Nakhon Ratchasima, Khon Kaen, Udon Thani, and ends in Nong Khai, where it links with the Thai-Lao Friendship Bridge to Laos.


  1. ^ Baker, Chris; Phongpaichit, Pasuk (2009). A History of Thailand (2nd, paper ed.). Cambridge University Press. p. 156. ISBN 9780521759151.
  2. ^ Keyes, Charles F (March 1967). "Isan: Regionalism in Northeastern Thailand". Cornell Thailand Project; Interim Reports Series, No. 10 (PDF). Ithaca: Department of Asian Studies, Cornell University. Retrieved 16 August 2019.