Nan is one of Thailand's most isolated provinces, covered in thick forested mountains and endowed with rich river valleys. It is the eastern edge of the Lanna Kingdom on the Thai border with Laos. The province is sandwiched between Chiang Rai and Phrae provinces to the west and Laos to the east. The provincial capital of Nan is situated on the banks of the River Nan - the third longest river in Thailand at 627 km. Nestled in a valley and surrounded by mountain, this geographic location that won in its nickname of "the closed city". It was once the centre of an independent kingdom that had little association with its neighbours. The term "Nan" is believed to derive from the word Naga (the water god based on native legend and belief. In the mid 13th century, gathered together with several other small states, the more powerful Nanthaburi was formed. An association with the Sukhothai kingdom was formed, but its remoteness allowed the state a considerable amount of independence. In the latter part of the 14th century it became a principality of the northern Lanna Thai kingdom and continued to flourish through to the 15th century. However, in 1587 the Burmese wrestled control of the kingdom, transporting many of the inhabitants to Burma to become slaves. Nan became barren and all but abandoned up until the end of the 18th century. Because of its geographic, the winds of change have had little impact on its civilization, compared with neighboring provinces.

Wat Phumintr is the most famous temple in Nan. With its unusual cruciform viharn, which is surrounded by bei sema (boundary stones marking consecrated ground). It was constructed in 1596, and was restored extensively between 1865 and 1873. The interior walls of the viharn are adorned with interesting murals, with scenes of the lifestyle of the period, painted by Thai Leu artists during restoration.

Mural paintings at Wat Phumintr are impressive in that they consist of life-style, beautifully painted pictures of men and women wearing ornaments. The portraits express feelings on the faces of the people, who look alive with movements.