The wreck of a scow.
In 1918, a scow (barge) broke away from its tow on the Niagara river with two crewmen on board. Fortunately it got stuck on rocks just upstream of the Horseshoe Falls, sparking an amazing rescue.
The scow is near the left of the picture, just to the right of the bushes in the river. The old powerhouse building is on the right. Taken from the Canadian side of the Horseshoe Falls
The scow in the centre of the picture, taken from a jellycoptor.
The story of the rescue.
http://www.niagarafrontier.com/scow.html