From some googling:
"Mrs. Collins said....You just see two missing bikes and a purse thrown up over a chain-linked fence and you see nothing else, we just feel that they were taken.
One report said:
The found purse side of the chain link fence is on the interstate side of the fence.
Another report said:
Collins purse and cell phone were found on the other side of a fence about 20 feet from where their bikes were located.
http://www.hlntv.com/article/2012/07/16/missing-iowa-cousins-vanish-while-riding-bikes
One girls purse with a cell phone she stored music on which was not activated was found near the area on the other side of the fence closer to the Interstate,
Where the girls bikes were found, it would be incredibly difficult to get them out of there without any people who frequent the lake or the trails or live on the lake and the trails. However ATVs are allowed back there and there IS A LARGE section of fence that a car appeared to have driven through this winter still not repaired. Search and rescue dogs lost the scent of the girls at the bikes
http://www.northiowatoday.com/?p=28818
It was reported three different ways:
1. other side of the fence to the highway
2. other side of the fence to the lake
3. 20 feet away