 The Prairie Dog Town Fork Red River joins with Buck Creek in the northwestern corner of the county to form the Red River, which flows east to form the northern border of the county, separating it from Oklahoma.Hardeman County is the northernmost county in Texas that is not part of the Texas Panhandle.As of the census of 2000, there were 4,724 people, 1,943 households, and 1,319 families residing in the county.