Rattlesnake Lake is an artifact from the Cedar River Dam. The water is seepage from the real dam, and it just accumulates in this bowl shaped depression.
The mountain is called Rattlesname Ledge. I didn't verify the accuracy of the name.
There is a boat launching ramp on the lake, and here it is.
And there's wild life there too - just above the large stump in the foreground.
This tree has returned to life - I presume it was cut down at some stage, and then the stump has started growing again, or else a new seedling took root in the stump. But the branches don't match the size of the stump.
I believe that is Mt. Si, one of the Twin Peaks from the TV series, which was shot at North Bend.
Cedar Falls
2000