Aside from the arbitrarily designated 49th parallel for much of the border there are several physical features. Starting from the west and going east:
The US/Canadian border is several thousand miles long. There are many features along its length.
From Minnesota to Washington state it is the 15th north parallel.
The great Lakes
The Great Lakes are part of the border between the USA and Canada.
Canada is part of North America. Niagara Falls is part of the border between Canada and the US.
A physical feature that forms part of the border of New York State is Lake Ontario. If you mean the border around New York City, a physical feature would be the Hudson River.
Alaska borders the far northwest of Canada.
The State of Alaska, which is part of the United States, has a border with the northwestern region of Canada.
wrong
wrong
The Yukon River crosses the Canada-US border, but does not form part of it.
The Great Lakes are part of the border between the USA and Canada.
Canada is on the north in relation to the US. The southern part of Canada forms the border with the northern part of United States.
Canada or Mexico
No. Canada shares a border with the United States of America and is not part of Europe.