Buffalo Rock State Park& Effigy Tumuli is an Illinois state park on 298 acres in LaSalle County, Illinois, United States. The park sits across the Illinois River from Starved Rock State Park, just south of the Illinois and Michigan Canal trail. According to legend, it was once used as a "blind canyon" for Indians to capture buffalo. Effigy Tumuli, an art exhibit on the park property, consists of five earth art animal sculptures native to the Illinois River.