Kana:takon

A Tiny Piece of Canada Attached to the United States

Pictured above is the border between the United States and Canada. To the south, you see the State of New York. To the north, you see the provinces of Quebec and Ontario. You'll notice that there's a slice of land north of the border that is not attached by land to Canada. Let's take a closer look.

This exclave is called Kana:takon. It's less than a square mile in area. The story of how it ended up Canadian instead of American goes back to the 1783 Treaty of Paris, the first attempt to define the boundaries of the nascent United States of America. That treaty's lengthy description of the border said that this area would be divided by the middle of the St. Lawrence River to the 45°N line of latitude.
These were decisions made by people with limited knowledge of the actual geography and, by modern standards, inadequate surveying equipment. As I've mentioned previously, such problems led the United States to accidentally build a fort in Canada.
The Great Lakes and the St. Lawrence River have numerous islands. It was not always clear from the Treaty of Paris which islands belonged to which nation. But boundary commissions worked during the 1830s and resolved the outstanding issues by the 1842 Webster-Ashburton Treaty. St. Regis, as Kana:takon was known at the time, would remain Canadian.
The entire territory is part of a Mohawk Native American/First Nations community that straddles the US-Canadian border. Members of that nation cross the international border freely because the 1794 Jay Treaty permits them to do so:

It is agreed that it shall at all Times be free to His Majesty's Subjects, and to the Citizens of the United States, and also to the Indians dwelling on either side of the said Boundary Line freely to pass and repass by Land, or Inland Navigation, into the respective Territories and Countries of the Two Parties on the Continent of America (the Country within the Limits of the Hudson's Bay Company only excepted) and to navigate all the Lakes, Rivers, and waters thereof, and freely to carry on trade and commerce with each other.

Kana:takon is a thriving community with its own school, homes, and businesses. It's easy to walk or drive into the United States. But though it's part of Canada, residents must drive through the United States to get to Canada.