Point Roberts, Washington - it takes two border crossings to get there, and two more to get home, but worth the trip (partly because we had never been there before). It is about 5 square miles of land, with water on three sides and Canada on the north side. See this link for a view of it all and how it came about.
We were already in Sumas, WA (and lots of farming and gardening to admire there). This was our chance to cross the border at Sumas and drive west through Canada to Point Roberts.
DH - inspecting a likely geocache hiding spot at Lighthouse Marine Park.
There is a small community, a marina and usually a lot of Canadians. On this Thursday afternoon, there weren't many others around.
Here is a cache DH found at a different spot in the park. DH will move the travel bug (the lady bug, in this case) to a different cache. The owner can follow it around the world.