Sorry for the obsession with aerial maps, but the thing I've had the hardest time with regarding this case is the logistics-
I am interested in how the perp accessed and exited the area because I feel this speaks to planning and familiarity. I'm assuming he used a vehicle, so he had to park it somewhere. On a broad level, he could only park East or West of the bridge/trail and North or South of the river.
Initially, I felt the most likely place to park would be the SW corner of the cemetery in the wooded area. This makes sense because it provides for some cover, it is an area that isn't too alarming to park a car if someone happened upon it. It also requires the least amount of foot travel to the bridge and out of the area after the crime and is the main reason that I feel this would speak to planning as I would imagine he'd want to exit the area quickly after committing the crime. This positioning of a vehicle would render it unnecessary for him to cross the bridge at all, but doesn't mean that he wouldn't do so to blend in or to get in a position that he felt he could best intercept them. It could also be a situation of random opportunity, but that would raise different questions. At this point, I feel this position of a vehicle to be one of the more likely ones, mainly because I feel he took them to where he did for some reason and part of that would have to do with being able to escape unnoticed. This position would mean he would have the least likelihood of coming into contact with a witness after the crime because it wouldn't require him to cross the trail or get near the bridge before leaving.
The 2nd most likely position to park a car is one that I didn't notice at first until I zoomed in. There is a driveway off of W 300N that intersects the monon bridge trail. I've shaded it in white. Looking closer, it crosses the trail and appears large enough for a vehicle. It goes roughly parallel to the monon trail down toward the river. I remember one of the witnesses interviewed that saw a man, but not the girls, mentioned that she did not take the trail to the right. At first I assumed that meant the trail that intersected the bridge trail on the south end of the bridge, but it could actually be the shaded trail on the North side of the Creek. If one were walking toward the bridge, it would be on the right. It does appear to me that someone could have driven a car down there, but it would be a little more conspicuous if a witness were to happen upon it. This position would also require the perp to cross the trail after the crime to get back to his car and pull out of the area where it is possible to encounter witnesses. Again, if it were more of an opportunistic situation, this might not have been planned for or perhaps would speak to the level of sophistication based upon the level of risk taken.
There are also several areas(blue arrows) South of the bridge that it appears a vehicle could have been placed. These would indicate to me less sophistication or planning because it means he'd have to risk crossing the bridge after the crime and risk being seen. It would also have him parked on a drive that serves a private residence which would make a vehicle stand out, even risk being called in as a trespasser. This would, however, require him to cross the bridge twice unless he crossed the creek itself and in 40 degree weather and seeing the depth of it in most places, I doubt this.
I'd like to hear some others' thoughts on this. The fact that there is no description of a vehicle of interest leads me to believe that he either didn't use one which I find unlikely or that he didn't park in a spot that anyone else came across while his vehicle would have been there. This rules out a few of the more common areas, because any vehicle seen by a witness has been checked into by law-enforcement and I'd bet if there was a vehicle that couldn't be identified, then I feel they may have released info to the public to try to locate it. Back to work... More maps-