France
france
The continent that extends the furthest west is North America. On the other hand, the continent that extends the furthest east is Asia.
The Yukon Territory.
Virginia
Norway and Iceland
The US State of Virginia extends further west than either West Virginia or New York.
If you mean the island chain that extends from Alaska, that would be the Aleutian Islands. Note that the farthest west Aleutian island is closer to Tokyo than it is to Anchorage!
British Columbia is the Canadian province farthest West.
Kentucky is the farthest west.
Siberia is the farthest west territory. (It's also the farthest east, depending on which way matters to you)
Lake Superior is farthest west.
In the contiguous 48 states, Minnesota extends slightly farther north than other western states (Washington, Idaho, Montana, North Dakota).The farthest south is Florida, where the Keys extend below 25°N latitude, the approximate southern limit of Texas.
Colorado is the farthest state west of the four examples.