# Straight-lined international and interior borders

**URL:** <https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484>\
**Category:** Factual Questions\
**Created:** [January 2, 2025, 3:43pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484 "2025-01-02T15:43:50Z")\
**Posts on this page:** 20\
**Page:** 5

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**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\
**Post date:** [December 27, 2025, 1:11am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/81 "2025-12-27T01:11:49Z")

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My wife graduated from Western Reserve University (now Case-Western Reserve) The first day of student orientation included explaining what a “Western Reserve” was.

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**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\
**Post date:** [December 27, 2025, 2:30am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/82 "2025-12-27T02:30:39Z")

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> [@John\_DiFool](#):
>
> Using rivers as borders can be troublesome over time as rivers, esp. ones in flat floodplains, tend to change their course pretty frequently.

Yea, if you’re on the Ohio River, you should never assume which state you’re in.

[![](https://live.staticflickr.com/65535/55007385503_965a620185_w.jpg) ](https://live.staticflickr.com/65535/55007385503_965a620185_w.jpg)

[![](https://live.staticflickr.com/65535/55007482474_df8a2ef2bc_w.jpg) ](https://live.staticflickr.com/65535/55007482474_df8a2ef2bc_w.jpg)

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**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\
**Post date:** [December 27, 2025, 2:39am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/83 "2025-12-27T02:39:57Z")

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[Some states came very close to war over border disputes](https://en.wikipedia.org/wiki/Toledo_War).

Michigan got the last laughs, with getting the UP and all.

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**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\
**Post date:** [December 27, 2025, 3:12am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/84 "2025-12-27T03:12:47Z")

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> [@Crafter\_Man](#):
>
> Yea, if you’re on the Ohio River, you should never assume which state you’re in.

The Ohio, like the Potomac, had the original border set along the one bank, rather than through the deepest channel or center as in most river borders. In the case of the Ohio, it was the northern bank, rather than the southern one like the Potomac. The Chattahoochee River also had the original border between Alabama and Georgia set along one bank, the western one, in that case.

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**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\
**Post date:** [December 27, 2025, 3:27am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/85 "2025-12-27T03:27:31Z")

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Looking at Google Maps, though, why did Ohio get so screwed? The border is almost always along the Ohio bank/shoreline.

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**Author:** ![Q.Q.Switcheroo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/q.q.switcheroo/32/5713_2.png) [@Q.Q.Switcheroo](https://boards.straightdope.com/u/Q.Q.Switcheroo)\
**Post date:** [December 27, 2025, 3:32am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/86 "2025-12-27T03:32:58Z")

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Much as Senegal got screwed when the colonizers drew The Gambia’s entire border around the river.

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**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\
**Post date:** [December 27, 2025, 3:49am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/87 "2025-12-27T03:49:35Z")

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> [@Crafter\_Man](#):
>
> Looking at Google Maps, though, why did Ohio get so screwed? The border is almost always along the Ohio bank/shoreline.

You didn’t pay attention to the post directly above yours. I’ll repeat: the original border was drawn along the northern bank of the river. As for who did it, I think Charles II or whichever king was friendly with Lord Baltimore. He gave all the Potomac to Maryland and all the Ohio to Virginia as compensation. At least that’s my understanding of what happened.

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**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\
**Post date:** [December 27, 2025, 3:59am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/88 "2025-12-27T03:59:41Z")

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> [@Q.Q.Switcheroo](#):
>
> Much as Senegal got screwed when the colonizers drew The Gambia’s entire border around the river.

That’s another interesting border drawing. The eastern part of that border was drawn ten miles away from the navigible part of the river. Why ten miles and why only the navigible part? Ten miles was the range of the best ship in the British Navy at the time. (I forget the name of the vessel off hand.) That also explains why only the navigible part of the river. The river actually goes further east, past the border, but it wasn’t navigible by that ship.

One wonders if they actually sent the ship upriver, firing off boundary markers from its guns. But I suspect they didn’t do that.

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**Author:** ![Ancient\_Nerd](https://avatars.discourse-cdn.com/v4/letter/a/ed655f/32.png) [@Ancient\_Nerd](https://boards.straightdope.com/u/Ancient_Nerd)\
**Post date:** [December 27, 2025, 6:43am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/89 "2025-12-27T06:43:34Z")

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Cities tend to grow on rivers, often on both sides. If a river is a border, that splits the city between two political entities.

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**Author:** ![Lord\_Feldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lord_feldon/32/341_2.png) [@Lord\_Feldon](https://boards.straightdope.com/u/Lord_Feldon)\
**Post date:** [December 27, 2025, 7:02am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/90 "2025-12-27T07:02:48Z")

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> [@dtilque](#):
>
> As for who did it, I think Charles II or whichever king was friendly with Lord Baltimore.

It was later than that. Virginia claimed land on both sides of the river until after the revolution. It eventually ceded the land north of the river, but not the river itself.

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<div class="post-metadata">

**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\
**Post date:** [December 27, 2025, 8:05am UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/91 "2025-12-27T08:05:19Z")

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> [@Lord\_Feldon](#):
>
> It was later than that. Virginia claimed land on both sides of the river until after the revolution. It eventually ceded the land north of the river, but not the river itself.

My point was where Maryland got the claim to the entire river, not how the dispute was settled. And I had the king wrong; it was Charles I who gave Maryland, including the river, to Lord Baltimore. This was in 1632. The dispute over the border was not a simple thing:

> **[A River Divided: Who Owns the Potomac River? - Hancock News](https://www.thehancocknews.com/2025/08/19/a-river-divided-who-owns-the-potomac-river/)**
>
> by Michael Nardolilli, Executive Director of the Interstate Commission on the Potomac River Basin Why are the state boundary lines along the Potomac River so irregular? Why doesn’t the line run neatly down the middle of the river, as it does in many...

> [@](#):
>
> Ownership of the Potomac River was entangled in three conflicting colonial land grants that reflected the lack of knowledge about the watershed by the newly arrived inhabitants.

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<div class="post-metadata">

**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [December 27, 2025, 3:18pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/92 "2025-12-27T15:18:38Z")

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> [@engineer\_comp\_geek](#):
>
> There is a commonly told story that the northern panhandle exists because that’s where Mason and Dixon ran into Indians and had to turn north to avoid them. That’s a complete falsehood, though a lot of folks seem to believe it.

I’ve heard a similar story about the Montana-Idaho border. Supposedly, the border was originally supposed to follow the Continental Divide, and at first, it does. But a divide is a global feature, not a local one, so when one ridgeline splits into two, it’s not always easy to tell which is the right one. The story is that they thought they were following the divide, until a river crossed their path (which couldn’t happen with the real Divide), so that’s when they realized that they had gone astray at some unknown prior point, and rather than going back and figuring it out, they just went straight north from there.

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**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\
**Post date:** [December 27, 2025, 4:38pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/93 "2025-12-27T16:38:53Z")

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True enough.

But rivers have been used as borders since forever. They are one of the few obvious lines in nature. yes, they shift over time. But it’s only in the last relatively short time, ~300 years, that the idea of rigid-forever borders became practically doable.

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**Author:** ![Mark\_Finn](https://avatars.discourse-cdn.com/v4/letter/m/34f0e0/32.png) [@Mark\_Finn](https://boards.straightdope.com/u/Mark_Finn)\
**Post date:** [December 27, 2025, 10:44pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/94 "2025-12-27T22:44:12Z")

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The Internet told me that Ontario shares a 1,682 mile (2,727 km) border with various US states. The article claims that the border runs entirely on water with the exception of less than a 1 mile (1 km) land border. If this is true - where is this tiny land border?

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<div class="post-metadata">

**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\
**Post date:** [December 27, 2025, 11:08pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/95 "2025-12-27T23:08:13Z")

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> [@Mark\_Finn](#):
>
> If this is true - where is this tiny land border?

Google’s bullshit generator seems to think it’s true, and gave this response:

> [@](#):
>
> The Ontario-US border is mostly water (Great Lakes/St. Lawrence River) but has small land sections, mainly around the Lake of the Woods area, featuring portages like Height of Land, Watap, and [Monument Portage](https://www.google.com/search?q=Monument+Portage&newwindow=1&sca_esv=2d67cf3da2c4fbe1&rlz=1C1CHBD_enUS847US847&sxsrf=AE3TifMgVmce3LvpFUStIiWFo6TomkHNYA%3A1766876389079&ei=5WRQaaHXBMKjptQPv7vHwQc&ved=2ahUKEwjb0KfM796RAxUQrYkEHXlsBUYQgK4QegQIARAE&uact=5&oq=ontario+us+border+where+land&gs_lp=Egxnd3Mtd2l6LXNlcnAiHG9udGFyaW8gdXMgYm9yZGVyIHdoZXJlIGxhbmQyBRAhGKABMgUQIRigATIFECEYoAEyBRAhGKABMgUQIRifBUifRVCwAVj_QnAEeAGQAQCYAYcBoAHFC6oBAzYuOLgBA8gBAPgBAZgCEqACtwzCAgoQABiwAxjWBBhHwgIEECMYJ8ICChAAGIAEGEMYigXCAgsQABiABBiRAhiKBcICBRAAGIAEwgIGEAAYFhgewgIIEAAYogQYiQXCAggQABiABBiiBMICCBAAGBYYChgewgIFECEYqwLCAgsQABiABBiGAxiKBcICBRAAGO8FmAMAiAYBkAYIkgcENC4xNKAHjmKyBwQwLjE0uAedDMIHBjAuMS4xN8gHVIAIAA&sclient=gws-wiz-serp&mstk=AUtExfBqtdYY8QqpqvJF-GsOQObRUNurEJNykVTOAQQqmR0b9hEK8XHFNbCGqaY5VF-YYFRvQVJoRaGToBKCs4EPnrnpXyUzqogX7SxqbsKYMQUi26patX-ny8I4rXX0sG9UyZfyJJ3faTeGsp8BX2EtzECWBOakPleeL95ioqRsIBDBDzCWsvDFV-UE16u9BnMumxVD7kYRGhJLi-PaBKl_H9vplRtqRYzGfHaV-4roZ2zC4D_LGEbKRWeCSbMPUyR8IAiTkMrX6WW4OILTBFaxeuXySEiRQa0nDbelJUYcLd91MA&csui=3), which are crucial parts of the ~1 km total land border in that remote region, with major crossings like Niagara Falls and Detroit-Windsor being famous water-linked points.
> 
> **Key Land Border Areas:**
> 
> - **Lake of the Woods Area (West):** This is where most of the land border in Ontario lies. It’s defined by a series of lakes and portages (carrying routes for canoes) rather than a straight line.
> - **[Height of Land Portage](https://www.google.com/search?q=Height+of+Land+Portage&newwindow=1&sca_esv=2d67cf3da2c4fbe1&rlz=1C1CHBD_enUS847US847&sxsrf=AE3TifMgVmce3LvpFUStIiWFo6TomkHNYA%3A1766876389079&ei=5WRQaaHXBMKjptQPv7vHwQc&ved=2ahUKEwjb0KfM796RAxUQrYkEHXlsBUYQgK4QegQIAxAC&uact=5&oq=ontario+us+border+where+land&gs_lp=Egxnd3Mtd2l6LXNlcnAiHG9udGFyaW8gdXMgYm9yZGVyIHdoZXJlIGxhbmQyBRAhGKABMgUQIRigATIFECEYoAEyBRAhGKABMgUQIRifBUifRVCwAVj_QnAEeAGQAQCYAYcBoAHFC6oBAzYuOLgBA8gBAPgBAZgCEqACtwzCAgoQABiwAxjWBBhHwgIEECMYJ8ICChAAGIAEGEMYigXCAgsQABiABBiRAhiKBcICBRAAGIAEwgIGEAAYFhgewgIIEAAYogQYiQXCAggQABiABBiiBMICCBAAGBYYChgewgIFECEYqwLCAgsQABiABBiGAxiKBcICBRAAGO8FmAMAiAYBkAYIkgcENC4xNKAHjmKyBwQwLjE0uAedDMIHBjAuMS4xN8gHVIAIAA&sclient=gws-wiz-serp&mstk=AUtExfBqtdYY8QqpqvJF-GsOQObRUNurEJNykVTOAQQqmR0b9hEK8XHFNbCGqaY5VF-YYFRvQVJoRaGToBKCs4EPnrnpXyUzqogX7SxqbsKYMQUi26patX-ny8I4rXX0sG9UyZfyJJ3faTeGsp8BX2EtzECWBOakPleeL95ioqRsIBDBDzCWsvDFV-UE16u9BnMumxVD7kYRGhJLi-PaBKl_H9vplRtqRYzGfHaV-4roZ2zC4D_LGEbKRWeCSbMPUyR8IAiTkMrX6WW4OILTBFaxeuXySEiRQa0nDbelJUYcLd91MA&csui=3):** A significant 400-meter land section.
> - **[Watap Portage](https://www.google.com/search?q=Watap+Portage&newwindow=1&sca_esv=2d67cf3da2c4fbe1&rlz=1C1CHBD_enUS847US847&sxsrf=AE3TifMgVmce3LvpFUStIiWFo6TomkHNYA%3A1766876389079&ei=5WRQaaHXBMKjptQPv7vHwQc&ved=2ahUKEwjb0KfM796RAxUQrYkEHXlsBUYQgK4QegQIAxAE&uact=5&oq=ontario+us+border+where+land&gs_lp=Egxnd3Mtd2l6LXNlcnAiHG9udGFyaW8gdXMgYm9yZGVyIHdoZXJlIGxhbmQyBRAhGKABMgUQIRigATIFECEYoAEyBRAhGKABMgUQIRifBUifRVCwAVj_QnAEeAGQAQCYAYcBoAHFC6oBAzYuOLgBA8gBAPgBAZgCEqACtwzCAgoQABiwAxjWBBhHwgIEECMYJ8ICChAAGIAEGEMYigXCAgsQABiABBiRAhiKBcICBRAAGIAEwgIGEAAYFhgewgIIEAAYogQYiQXCAggQABiABBiiBMICCBAAGBYYChgewgIFECEYqwLCAgsQABiABBiGAxiKBcICBRAAGO8FmAMAiAYBkAYIkgcENC4xNKAHjmKyBwQwLjE0uAedDMIHBjAuMS4xN8gHVIAIAA&sclient=gws-wiz-serp&mstk=AUtExfBqtdYY8QqpqvJF-GsOQObRUNurEJNykVTOAQQqmR0b9hEK8XHFNbCGqaY5VF-YYFRvQVJoRaGToBKCs4EPnrnpXyUzqogX7SxqbsKYMQUi26patX-ny8I4rXX0sG9UyZfyJJ3faTeGsp8BX2EtzECWBOakPleeL95ioqRsIBDBDzCWsvDFV-UE16u9BnMumxVD7kYRGhJLi-PaBKl_H9vplRtqRYzGfHaV-4roZ2zC4D_LGEbKRWeCSbMPUyR8IAiTkMrX6WW4OILTBFaxeuXySEiRQa0nDbelJUYcLd91MA&csui=3) & [Monument Portage](https://www.google.com/search?q=Monument+Portage&newwindow=1&sca_esv=2d67cf3da2c4fbe1&rlz=1C1CHBD_enUS847US847&sxsrf=AE3TifMgVmce3LvpFUStIiWFo6TomkHNYA%3A1766876389079&ei=5WRQaaHXBMKjptQPv7vHwQc&ved=2ahUKEwjb0KfM796RAxUQrYkEHXlsBUYQgK4QegQIAxAF&uact=5&oq=ontario+us+border+where+land&gs_lp=Egxnd3Mtd2l6LXNlcnAiHG9udGFyaW8gdXMgYm9yZGVyIHdoZXJlIGxhbmQyBRAhGKABMgUQIRigATIFECEYoAEyBRAhGKABMgUQIRifBUifRVCwAVj_QnAEeAGQAQCYAYcBoAHFC6oBAzYuOLgBA8gBAPgBAZgCEqACtwzCAgoQABiwAxjWBBhHwgIEECMYJ8ICChAAGIAEGEMYigXCAgsQABiABBiRAhiKBcICBRAAGIAEwgIGEAAYFhgewgIIEAAYogQYiQXCAggQABiABBiiBMICCBAAGBYYChgewgIFECEYqwLCAgsQABiABBiGAxiKBcICBRAAGO8FmAMAiAYBkAYIkgcENC4xNKAHjmKyBwQwLjE0uAedDMIHBjAuMS4xN8gHVIAIAA&sclient=gws-wiz-serp&mstk=AUtExfBqtdYY8QqpqvJF-GsOQObRUNurEJNykVTOAQQqmR0b9hEK8XHFNbCGqaY5VF-YYFRvQVJoRaGToBKCs4EPnrnpXyUzqogX7SxqbsKYMQUi26patX-ny8I4rXX0sG9UyZfyJJ3faTeGsp8BX2EtzECWBOakPleeL95ioqRsIBDBDzCWsvDFV-UE16u9BnMumxVD7kYRGhJLi-PaBKl_H9vplRtqRYzGfHaV-4roZ2zC4D_LGEbKRWeCSbMPUyR8IAiTkMrX6WW4OILTBFaxeuXySEiRQa0nDbelJUYcLd91MA&csui=3):** Other short land segments in this area.
> 
> - **Great Lakes & Rivers (East):** From the Lake of the Woods eastwards, the border follows water: the Pigeon River, Lake Superior, St. Marys River, Lake Huron, St. Clair River, Detroit River, Lake Erie, Niagara River, and the St. Lawrence River.

I found Height of Land Portage and Watap Portage on Google Maps, so this does appear to be accurate.

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<div class="post-metadata">

**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [December 27, 2025, 11:10pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/96 "2025-12-27T23:10:22Z")

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There are probably some other spots, though, where the border used to be a river, but the river has since changed its course enough to put the border on shore.

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<div class="post-metadata">

**Author:** ![TokyoBayer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tokyobayer/32/13989_2.png) [@TokyoBayer](https://boards.straightdope.com/u/TokyoBayer)\
**Post date:** [December 28, 2025, 1:18pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/97 "2025-12-28T13:18:36Z")

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> [@Chronos](#):
>
> Supposedly, the border was originally supposed to follow the Continental Divide, and at first, it does.

That’s a myth. The divide was following the Bitterroot Range and was established by act of Congress.

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<div class="post-metadata">

**Author:** ![commasense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/commasense/32/3017_2.png) [@commasense](https://boards.straightdope.com/u/commasense)\
**Post date:** [December 28, 2025, 3:12pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/98 "2025-12-28T15:12:27Z")

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Rather than start a separate thread that might cover much of the same ground surveyed here, I’d like to know how many other places in the world have circular borders, like the [Twelve-Mile Circle](https://en.wikipedia.org/wiki/Twelve-Mile_Circle) that forms the northern border of Delaware. That article points out that the borders of Plains, GA, and some other southern towns are full circles, but doesn’t discuss anything outside the U. S.

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**Author:** ![Schnitte](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/schnitte/32/9033_2.png) [@Schnitte](https://boards.straightdope.com/u/Schnitte)\
**Post date:** [December 28, 2025, 4:07pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/99 "2025-12-28T16:07:56Z")

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A short section of the border between Zimbabwe and Botswana is formed by a ten-mile circle centered on the town of Tuli, Zimbabwe. See here:

https://maps.google.com/maps?ll=-21.7278555,29.2560388&z=9&output=embed&dg=ntvb&q=Botsuana

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<div class="post-metadata">

**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\
**Post date:** [December 28, 2025, 4:32pm UTC](https://boards.straightdope.com/t/straight-lined-international-and-interior-borders/1012484/100 "2025-12-28T16:32:53Z")

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> [@commasense](#):
>
> Rather than start a separate thread that might cover much of the same ground surveyed here, I’d like to know how many other places in the world have circular borders

It’s already come up in this thread, but the border between Senegal and The Gambia has circular parts. As I said, the eastern part of that border is ten miles from the river. That makes for a wormlike profile with some circular sections where the river makes a turn. And then at the eastern end of navigation, there’s a semi-circle.

Just occured to me: The border between Massachusetts and New Hampshire is in part set as a displacement from a river. In this case it was 3 miles and I can’t remember the name of the river off-hand. But like the Senegal-Gambia case, there is probably some circular sections where the river makes a turn.

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