I've mention here of Point Roberts on the US/Canada boarder but I
aven't seen any mention here of Lake of the Woods, that bit of
Minnesota that is only accessible through Canada. I found a little
bit that folks might find interesting.

http://maps.yahoo.com/py/maps.py?
Pyt=Tmap&addr=&city=Angle+Inlet&state=MN&slt=49.345300&sln=-
95.062500&name=&zip=&country=us&BFCat=&BFClient=&mag=7&desc=&cs=7&newm
ag=5&poititle=&poi=

Apparently this little blip along the 49th parallel was settled as
part of an 1818 compromise:

"Following the War of 1812 a boundary commission tackled the
conflicting claims in the area from Lake Superior to Lake of the
Woods, but no change was made in the Treaty of Ghent with respect to
the boundary beyond the Lake of the Woods. In 1818, however,
diplomentats settled this western line, adopting the forty-ninth
parallel as the boundary as far west as the Rockies. Since no line
could run straight west of LOTW to the Missisisippi, the Convention
of 1818 hit upon a simple solution, namely to run a line due south
from the NW point of LOTW to the forty-ninth parallel.....the
agreement of 1818 gave the US that curious projection of land known
as the NW Angle--American territory separated from the rest of the
land area of the US by Buffalo Bay, the southwestern arm of LOTW."
http://www.e-democracy.org/mn-politics-archive/9803/0113.html

Cheers,

Jonathan