Courtesy picture of Wikipedia
1)[Nakhon Sa Wan-Lampang-Payao]
along national highway #1 (Phahol Yothin Road). Then turn left to highway #32 (Asia Route) at Wang Noi district of Phra Na Khon Si Ayuddhaya province passing Sing Buri province, Chai Nat province, Nakhon Sa Wan province either Kamphaeng Phet province or Tak province respectively. Reaching to Lampang province and then from there reaching Payao province. Total distance is 969 kilometers.
2)[Nakhon Sa Wan-Pitsanulok]
driving the same way of above choice until reaching Nakhon Sa Wan province altered to use the highway #117 going ahead to Phitsanulok province. Then turn to drive highway #11 so far as passing Uttaladit province till reaching Den Chai district. Then turn to highway #101 (Phrae-Nan) driving along this route till reaching Rong Kwang district. After that turning to highway # 103 gearing along the road for meeting the Pahol Yothin Road (highway #1) at Ngao district. Aim to Payao province respectively. Total distance is 782 kilometers.
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