The hole is 10 inches wide, 5 feet deep and is clearly visible about halfway up the sand dune, near the spot Nathan Woessner survived burial in 11 feet of sand until his rescue, Bruce Rowe of the Indiana Dunes National Lakeshore said.
"The hole is almost completely round. For this one they didn't need the ground-penetrating radar," Rowe said.
The discovery of the hole Monday could help determine what these natural phenomena are and how they form, and could answer the question of how the boy survived for four hours while buried under the sand, the Chicago Tribune reported Wednesday.
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