Buffalo Rock State Park is located on a bluff overlooking the Illinois River.   It is off Dee Bennett Road between Ottawa and Utica, Illinois.
     A portion of the land was the site of strip mining for coal in the 1930’s.  As a result of this mining, the land was polluted, eroded and barren.  The President of the Ottawa Silica Company (owned the property) commissioned Michael Heizer in 1983 to create the Effigy Tumuli earthwork.  It was completed in 1985.  This consists of 5 mounds of land representing abstracted animal forms.  There is a snake, catfish, turtle, frog, and water strider. These are seen along a 1.5 mile path.  Mr. Heizer considered the  mounds reminiscent of Indian Burial Mounds common to the region.
     The individual mounds are huge: water strider 685 feet; frog 650 feet; catfish 770 feet; frog 340 feet; and snake 2,070 feet.  It is because of the size, erosion, and overgrowth of vegetation
that many of the shapes are not recognizable

Frog

Catfish

Catfish

Overview of the Illinois River