Canada? Where are you looking?
The map shown is the California-Arizona-Mexico border. The border between Arizona and Mexico is the Colorado River, which runs southward and veers slightly west.
Los Algodones is in Mexico. Run south from there. How do you get Canada?
Hell, run North, how do you get Canada before the US? 
Oh I see. Nevermind.
One of my perennial favorites: Kentucky Bend, a bit of Kentucky that is completely geographically separate from the rest of the state. It cannot be gotten to from the rest of Kentucky without going through another state, not by land, water, or air.
Similarly, Kaskaskia, Illinois (pop. 9), the only piece of the state lying west of the Mississippi. The locals demanded the old border be preserved after a flood altered the river’s course, so Kaskaskia can only be reached through Missouri.
It was the subject of a Straight Dope sucker bet in 1976.
That doesn’t surprise me at all, but I had to look at the map and what does surprise me is that it runs SW to NE.
One league south of San Diego Bay to the intersection of the Gila and Colorado Rivers
Due to the border between Lake of the Woods and the Salish Sea lying on the 49th parallel, the phrase “49th parallel” is often used as a shorthand for the US-Canada border. However, the great majority of our population lives below the 49th parallel, including Ottawa, Montreal, and Toronto and all the other provincial capitals, except for the three prairie provinces (which are the only provinces entirely north of the 49th parallel).
The 49th parallel actually passes near such northern communities as Cochrane, Ontario, and Lebel-sur-Quévillon, Quebec.
(Much more accurate is the expression “north of 60” meaning the territories; however, parts of Nunavut – the islands in Hudson and James bays – are south of 60, and parts of Quebec and Newfoundland and Labrador are north of it.)
Stealing one of my favorite items of Canadian geograhical trivia: What is the northernmost province? (Quebec, owing to the Ungava Peninsula extending “north of 60”)
Here’s another one: Today, Canada’s only international land borders are with the U.S.; between 1867 and 1880, it could be said to have had land borders with the U.K. owing to the colonial territories only ceded in 1870 and 1880. With what one other nation has Canada had a land international boundary?
The Dominion of Newfoundland, between 1907 (when it got dominion status and 1934 (when it gave up self-rule owing to the Depression), and de jure up until it joined Confederation in 1949.
Yes, I thought Canada might have had a land boundary with Russia – but it only almost did. Russia sold Alaska to the US in 1867, and Canada acquired the Northwest Territory (including what is now Yukon) in 1870, so Canada missed out on a land boundary with Russia by 3 years!
Interesting bit of geographical trivia that never came to be: In 1977, the island of Martha’s Vineyard tried to secede from Massachusetts. It would have become a separate US territory, the 51st state, or part of another state. It got offers from both Vermont and Hawaii. If the latter came to pass, Hawaii would have been the only state to have islands in two oceans.
It came up in a previous thread of this sort, but does anybody have the inside skinny on why Delaware’s northern border is an arc? And what is the “center” of that arc? I have heard/read but forgotten and I know I could go look it up, but I just wanted to include it here as a mention in case others weren’t aware of it.
Another border anomaly that I have yet to see convincingly factual explanations for is that weird jog in the Tennessee-Kentucky border in the vicinity of “Land Between The Lakes.”
Yes, it always surprises me a bit that Pittsburgh is further east than Miami.
In 1682, Charles II granted William Penn various lands including the town of New Castle, “also called Delaware,” and all land within a twelve-mile circle of it. In 1704, reresentatives of the Upper Counties sought to meet more often than the Lower Counties wee willing to, and the two halves of Penn’s grant separated into what became Pennsylvania and Delaware. In 1750, the boundary between them was fixed by the terms of the 1682 grant as an arc of a circle 12 miles in diameter from the cupola of the New Castle courthouse. (As has been pointed out in previous threads, that circle also gives Delaware two small strips of land east of the Delaware River, bordering New Jersey.) (Relevant Wikipedia article.)
Wikipedia article on the Kentucky Bend. Apparently it was a case of someone laying down that land on the east bank of the Mississippi and north of a given parallel belonged to Kentucky, south to Tennessee – and when they finally surveyed the river bottoms they discovered the river dipped south of the parallel then came back north of it before continuing on south, leaving a small exclave of fertile bottomland north of the line and “east” of the river – i.e., on the east bank, though surrounded on three sides by riverbend.
I could swear I already thanked you for this, Earl Snake-Hips Tucker, but I must have moved on without the “Submit Reply” after I had previewed it.
Anyway, thanks! (again?)
What about the Colorado/Utah border continuing to the New Mexico/Arizona border?
It’s possible that the Hans Island situation will resolve itself with a land border across the island. At which point, Canada will have a land border with the country of Kalaalit Nunaat (Greenland) in the Kingdom of Denmark.
Thanks for both of these, Polycarp, and I see that I wasn’t clear about the TN-KY border thing. The “Kentucky Bend” thing is out on the western extreme of the border. What I was referring to is that jog in the east-west line that starts at “Land Between the Lakes” (just north of Dover) and goes north a little then west a little, then down sharply (south for maybe 10 miles) and then west again to the Mississippi. The two parts of the main east-west line dividing the two states differ in latitude by maybe 10 miles. I have yet to find anything definitive (and authoritative) on what went wrong with the surveying, if that’s what it was.
I meant the Mexico border to the Canada border. I wasn’t specific. Yours is a border-to-border thing, granted. But in light of the comparison to the E-W straight lines (neither of which are border-to-border) I see nothing that comes close to being a straight N-S line from Canada to Mexico.
I was surprised to learn that Wyoming does not actually exist.
Okay. I’ll bite.