Colo. Rev. Stat. § 30-5-145
All that part of Routt county as is included within the following described boundaries shall be set apart and is hereby established as a county, to be called the county of Moffat:
Beginning at a point on the north boundary of the state of Colorado at a point where said state line is intersected by the range line between ranges eighty-eight and eighty-nine west of the sixth principal meridian, known as the eleventh guide meridian; thence south on said range line to its intersection with the township line between township seven and eight; thence west on said township line to the section line between sections three and four, in township seven north, range eighty-nine west; thence south on said section line to the northeast corner of section twenty-eight in said township seven north, range eighty-nine west; thence west along the north line of sections twenty-eight, twenty-nine and thirty, in township seven north, range eighty-nine west of the sixth principal meridian to its intersection with the range line between ranges eighty-nine and ninety; thence south on said range line to its intersection with the north line of Rio Blanco county; thence west along the said north line of Rio Blanco county to its intersection with the line between the state of Utah and the state of Colorado; thence north on the said line between the state of Utah and the state of Colorado to the northwest corner of the state of Colorado; thence east on the line between the state of Wyoming and the state of Colorado to the point of beginning.
C.R.S. § 30-5-145