Exhibit building at Trego County fairgrounds, on east side of U.S. Highway 283 in WaKeeney, Kansas; seen from the southwest. – Ammodramus, CC0 – Wikimedia Commons Trego County is located in Kansas. About 2,808 people live here (as of 2020). Between 2010 and 2020, the population declined from 3,001 to 2,808. The area covers about 2,328.0 square kilometers. The region is divided into 2 Municipalities. The region was founded in 1879. Trego County is county in Kansas, United States. More information at TregoCountyKS.com.