This image was taken on board the famous Maid of the Mist, and features several landmarks visible along with the American Falls.
Plastichrome by Colorpicture, Boston, MA 02130
The description states:
NIAGARA FALLS, ONTARIO, CANADA
The American Falls, Cave of the Winds, and Rainbow Bridge, as seen from the “Maid of the Mist.”
–The cave is not obvious in the picture as it is behind the closest cataract, and the bridge is just visible in the extreme left background, behind the observation deck that extends from the American side.
This card dates from the 1960s.