The regions of northern Thailand.  Purple: Mae Hong Son Province.  Orange: Chiang Mai Province.  Yellow: Chiang Rai Province.  Blue:  Northern River Valleys.  Green: Lower Northern Thailand.
This map is based on a map by NordNordWest modified by Paul_012, File:BlankMap-Thailand-provinces.svg. That map is licensed CC-BY 3.0.
Own work
Douglas Paul Perkins