Cedar City, UT. Online Offers. Cedar City is a city in Iron County, Utah, United States, 250 miles (400 km) south of Salt Lake City on Interstate 15. It is the home of Southern Utah University, the Utah Shakespearean Festival, the Neil Simon Theatre Festival, the Utah Summer Games, and other events. As of the 2000 census, the city had a total population of 20,527. In 2007, the U.S. Census Bureau estimated Cedar City's population to be 27,823.