In the Frozen Swamp

Here are two interesting, manitou-like structures in a swamp overshadowed by a rocky slope.  These pictures were taken in winter because the swamp is impassable in warmer weather.  Up on the rocky slope is what looks like a manitou standing on a platform with rocks wedged underneath.

This looks like it was constructed for a purpose.  There's no obvious agricultural use.  Since it's uphill from a stream, perhaps it was a hunter's stand or lookout.
     On the ground in the swamp and further downstream is this structure, which also looks like it was constructed to fill a purpose. Perhaps firewood was stacked against it?