Peoria is the city that serves as the county's administrative center in Illinois, the United States. The city on the Illinois River had 113,150 residents as of the 2020 census. It is the hub of Central Illinois's 402,391-person Peoria Metropolitan Area, including Fulton, Marshall, Peoria, Stark, Tazewell, and Woodford. The Illinois State Archaeological Survey claims Henri de Tonti, a…