If you travel the Niagara Parkway between Fort Erie and Niagara on the Lake, you might have noticed small white bullet shaped concrete abutment spaced along the parkway. These are international boundary markers. Similar markers are found on the U.S. side of the border parallel to the Niagara River. To determine the exact location of the boundary between Canada and the United States surveyors would line up these markers to pin point the exact border in the middle of the Niagara River.
This is a bit of trivia for those who like this type of thing.