A monument to honour the fallen civil workers (police, government people, road construction workers) that did lost their lives while working in Nan in the 1950's to 1970's. It is on a small artificial hill along route 101. About 50m further is the Military Museum, but be aware that it is not always open. What means in Thailand that it is mostly closed. But if you are lucky there might be somebody to open the door for you.
You can go there all year around, daily, entrance is free. It is right along route 101, just 5 km before Thung Chang. From Nan town follow route 101 to Tha Wang Pha, Pua and Chiang Klang and then a few km before Thung Chang on your left hand side are the Military Museum & Memorial. For more information about Nan province see Destination Travel Guide Nan.