There are no longer signs marking the way. These mounds are on private property.

Indian Burial Ground Become a Museum
Thursday, May 15, 1930

The Chief Senachwine mounds, "happy hunting ground" of Chief Senachwine, and hundreds of his Pottawatomie braves, who in the early nineteenth century dominated this section of Illinois, has been converted into a park which was opened to the public last week by Walter Winship and George Wheeler, owners of the land upon which the mounds are located, one-half mile north of the village of Putnam.

Between seven and eight acres of land are covered by the mounds, in which it is estimated that more than a thousand Indians are buried. Many of the mounds are from 12 to 15 feet high and contain scores of bodies superimposed upon each other in the grave. Mr. Wheeler has dug up 47 of the skeletons from the burial ground and one of them is on exhibition.

The owners of the Indian burial ground, both of whom are old residents of Putnam, have spent 35 years collecting Indian relics and during that time have amassed more than 5,000 specimens.
These they have placed in a museum near the mounds, and may also be inspected.
Included in the exhibit are 600 pieces of Indian money removed from Indian graves, arrows, spears, pipes, scalping knives, axes and many other relics of Indian life.
There is a stone axe of perfect shape, which weighs 20 pounds, and a number of smaller axes which weigh 12 to 15 pounds.
Mr. Wheeler and Mr. Winship have scoured the Illinois for a distance of five or six miles in either direction from Putnam in gathering their collection.

Hundreds of tourists have stopped at the mounds during the past few years and the owners have received so many compliments upon the spectacle that this year they decided to make the nominal charge of 25 cents for visiting the park and seeing the museum.
Signs have been erected on the state highway near Putnam pointing out the direction to the mounds, which are open on Sunday and every day during the week.

Taken from http://genealogytrails.com/ill/putnam/news/News.html

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