(IL-66-01) E. of Seaton, Ohio Grove Township, Mercer County, IL. 160th St. S. 0.75 miles from jct with 20th Av. E. of Seaton, E. on 15th Av. 3.9 miles to the crib on the N. side of the road. (N41 05.424 W90 42.554) Photo 10-22-10.