McKinney is a town in, and the county seat of Collin County, Texas,. It is the second-largest city in Collin County, after Plano. McKinney is about 32 miles north of Dallas. The most recent estimate for the population is more than 191,645. The total area of this town is 62 square miles. All the city and county were named after Collin McKinney, signer of the Texas Declaration of Independence, as well as a congressman for the Republic of Texas Red River region. He was the sponsor of a bill creating counties in the state's northern section.