"Mysterious holes that were discovered at an Indiana sand dune last year -- and which nearly swallowed a child -- will keep a Lake Michigan park closed indefinitely.
The National Park Service announced last week that Mt. Baldy in the Indiana Dunes National Lakeshore, about an hour from Chicago, will be closed for the summer and beyond. The decision was made after two new holes in the dunes were found.
'The continued development of these holes in the dune surface poses a serious risk to the public," Acting Superintendent Garry Traynham said in a statement.
Scientists have been unable to determine how the holes, which seem to appear and disappear within a day, are formed in the 43-acre dune."