Okay, I'm going to do my best describe what I am asking you guys. My question is, What does a river ledge look like on a topo map? Im trying to use Navionics Webapp to find some river ledges for next summer, but I can't find what I'm looking for. The whole river obviously is a continuous ledge, but all I am seeing is a the river run the whole length of the lake. Can you guys throw some screen shots of what a good summer time river ledge looks like on a topo map? Thanks guys

The river ledge is just as you say. The edge of the river or sides. On the map it will be where the contour lines are closest together. 

Now for your other question about a good summer ledge. This will more than likely be different for every body of water but I seem to find the most fish on Creek ledges right next to a flat and not too far away from main river channel. Hope this helps

Finding ledges off a topo map is going to be, dare I say, impossible. A heavy jig and a lot of patience. 

  

 

Navionics

 

If you do a sonar channel profile like this small creek, the fish would most likely relate to the ledge side with the most vertical shape (the right side):