The "Identity of Nan Museum" in Nan
It is a modern & professional museum about the history of Nan province. It starts with the pre-historical time-line of the area of what we now call Nan province. Slowly the time-line goes to the settlement of Nan town.
An interesting part is where the many ethnic minorities are shown with the different traditional cloths. You can even make a photo of yourself dressed in any of the traditional cloths.
There is one (but major) problem for people who can not read Thai .... no signs or explanation in English (or any other language). The museum is open every day from 9:00 - 16:00 and entrance fee is 50 Thai Baht per person. For what we did get an personal Thai speaking guide. As the museum is located just outside of Nan town you might need your own transport (a bit too far for walking).