Phahonyothin Road
In Bangkok, Phahonyothin Road originates in Ratchathewi district and crosses Phaya Thai, Chatuchak, Bang Khen, and Don Mueang districts before continuing into Pathum Thani Province, and on through Ayutthaya, Saraburi, Lopburi, Nakhon Sawan, Chainat, again through Nakhon Sawan, Kamphaeng Phet, Tak, Lampang, Phayao and finally Chiang Rai, ending in Mae Sai district, where it connects to Tachileik in Myanmar.