Jefferson County, Jefferson Territory - County Territory

County Territory

According to historical description Jefferson County occupied an area bounded by the South Platte River to the east, the 40th parallel to the north, Bear Creek to the south, and 10 miles west of Bear Creek to the west, encompassing territory in modern-day Jefferson County, Adams County, Denver County, Boulder County, Clear Creek County, and Gilpin County. The townsite of Highland at the eastern edge along the South Platte was excluded from its borders. Its boundaries were set in Chapter X of the General Acts of the Territory of Jefferson which declared:

That the territory comprised within the following limits, be erected into a county to be called Jefferson: commencing at a point on the 40th parallel of north latitude where it is crossed by the main channel of the south fork of the Platte River, thence up the main channel of said stream to the mouth of Clear Creek, to the mouth of Ralston's Creek; thence in a straight line to the point where the main channel of Montana Creek joins the south fork of the Platte, thence up said river to the mouth of the canon at the base of the mountains; thence west eight miles; thence north to where said line would intersect the south line of Jackson county; thence east to the south east corner of said Jackson county, thence north to the 40th parallel, thence east to the place of beginning.