It’s entirely likely you don’t spend a lot of time thinking about the International Date Line. But your willful ignorance of its existence doesn’t stop the IDL from marking the invisible north-south (and sometimes diagonal) line signifying the end of one calendar day and the beginning of the next, nor the global community’s recognition of this fact.

But, look, I’m not here to lecture you about science or history or international law, or anything like that (as enjoyable as that may be). No, what we’re really here for is an introduction to what may just be the most unique pair of islands in the entire world: the Diomedes. Found in the middle of the Bering Strait, which separates the easternmost portion of Russia from Alaska, this duo of rocky, mesa-like islands is unlike any other for two big reasons.

The first has to do with ownership. Big Diomede, the island to the left if you’re looking at the pair straight on, is part of Russia, while Little Diomede, to the right, is owned by the United States. The two were separated when Russia and the U.S. finalized the Alaska Purchase in 1867, and have been used ever since to designate the boundary between the countries.

What’s fun, though, is that during the winter, an ice bridge often forms between the two Diomedes, making it possible to walk from the U.S. to Russia, or vice versa. Unfortunately, such a feat is highly inadvisable, as crossing from one to the other is illegal (but, I mean, you could give it a try and see what happens?).

The other major reason we are talking about these little buggers is where our old pal, the International Date Line, comes back into play. Because on top of belonging to different countries, the Diomedes also sit on opposite sides of the IDL.

This means a couple of things, but first and foremost it means that Big Diomede, to the west, or left, of the IDL, is nearly a full day ahead of Little Diomede, which is why the larger island is sometimes referred to as “Tomorrow Island” and the smaller as “Yesterday Island.”

Due to technicalities that we won’t bother getting into, the actual difference between the two is 20 or 21 hours, depending on the time of year. So, if you could legally cross from one to the other, you would essentially be a time traveler. Head from Little Diomede to Big Diomede, right to left, and you’ve ventured from the past into the future; the other way around, and… well, you get the idea.

The other thing I can’t get out of my head re: the Diomedes is that, again, by virtue of their position right on top of the International Date Line, they literally sit right where east and west meet. We’ve already established what that means in terms of time zones and what have you, but this is the reason I keep saying “left” and “right” instead of the compass directions.

Because although Big Diomede sits to the west of Little Diomede, the line demarcating where “east” ends and “west” begins is right in between, meaning Big Diomede is as far east as east goes. Little Diomede, it follows, is as far west as west goes. But when you’re looking at them straight on from above — the satellite view, if you will — the larger island is physically west of the smaller. Let me say that again (but in a different way): the island that is as far east as east goes (Big Diomede) is found west of the island that is as far west as west goes (Little Diomede).

Are you understanding why this is blowing my mind? It’s okay if not. I get excited over silly things like zany geographical fun facts, but it’s cool if that’s not your thing (though I would question why you are reading this post in the first place, were that the case).

But back to the islands! Look, I know you’re probably never going to travel to the Diomedes. It’s likely I won’t either. However, if you did decide to make the trek to Little Diomede (America’s favorite Diomede, you might say), you would find yourself on a rock in the middle of the Bering Strait with a total area of just under three square miles that’s home to a population of less than 100 people — most of them, if not all, Iñupiat (indigenous Alaskans), and all of them hunkering down in the City of Diomede on the island’s western shore.

In the even unlikelier event that you opted to travel to Big Diomede, you would find yourself… alone. The larger island, which has an area of 11 square miles, has no permanent inhabitants. It’s been desolate in that way since the end of World War II, when Russia forced all of the Iñupiat residing there to take a hike. Though “desolate” is not entirely accurate, as Big Diomede is home to a weather station and a Russian border security base.

Barring your unlikely visit to this remote part of the world, you can at least take heart knowing you now have this odd geographical fact stored in your back pocket, ready to be unleashed in any number of settings or situations, that will surely — surely — impress a first date or the guys who hang around the water cooler in the office break room.

-LTH