this post was submitted on 28 Oct 2025
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Today I Learned

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When Sweden and Denmark built a connection between their countries, Sweden preferred a bridge, and Denmark preferred a tunnel, they each built their half and connected them in the middle with an artificial island. The Øresund Bridge is unique in the world.

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[–] 1985MustangCobra@lemmy.ca 17 points 1 day ago

canada needs this to go underneath the USA straight to mexico so we dont have to drive through that god forsaken country

[–] Schlemmy@lemmy.ml 8 points 1 day ago (1 children)

There's a good Scandinavian crime series named 'The Bridge'. It features this bridge.

[–] LumiNocta@lemmy.zip 9 points 1 day ago

I've driven over this bridge about 4 times. And each time I was in awe of the views and the architecture. It's a very nice drive but can be a bit scary when you're on the bridge with higher winds.

It brings you to Sweden from Denmark and vice versa ofcourse. It does cost some money to cross as it is a toll road.

[–] mercano@lemmy.world 64 points 2 days ago (2 children)

There’s one in Virginia, the Chesapeake Bay Bridge Tunnel. There are two tunnels segments to go under major shipping channels. There are major naval bases upstream, and it was considered a national security risk to have a fleet potential trapped behind a downed bridge.

[–] mountaincalledmonkey@sopuli.xyz 21 points 2 days ago (2 children)

along with the Hampton Roads Bridge-Tunnel right next door

[–] ray@sh.itjust.works 14 points 1 day ago

The Hong Kong-Zhuhai-Macau Bridge is another one. It's a bridge most of the way but there's one section that's a tunnel.

[–] prettybunnys@piefed.social 9 points 2 days ago* (last edited 1 day ago) (1 children)

Driving over from Hampton into Norfolk and seeing the carriers at dock is pretty cool.

Makes them look tiny relative to how large they actually are.

[–] higgsboson@piefed.social 7 points 1 day ago

By contrast standing 100ft away is more like looking up at a freaking skyscraper.

[–] Bebopalouie@lemmy.ca 1 points 1 day ago

I drove the Chesapeake Bay Bridge tunnel back in the 70’s with my mom on one of our trips.

[–] DupaCycki@lemmy.world 3 points 1 day ago

So you learned about one of the 50 such constructions in my Cities: Skylines city. Wait till you see the rest.

[–] someguy3@lemmy.world 22 points 1 day ago

The justification for the additional expenditure and complexity related to digging a tunnel for part of the way, rather than raising that section of the bridge, was to avoid interfering with air traffic from the nearby Copenhagen Airport, to provide a clear channel for ships in good weather or bad, and to prevent ice floes from blocking the strait. The bridge received the 2002 IABSE Outstanding Structure Award.

[–] IWW4@lemmy.zip 19 points 1 day ago (2 children)

That bridge it not unique at all. There is one in Virginia.

[–] allan@lemmy.blahaj.zone 6 points 1 day ago (1 children)

Every bridge is unique in the world, probably! But yeah, a silly sentence...

[–] IWW4@lemmy.zip 3 points 1 day ago

That is actually a very good point. All bridges are unique to the environment they are built and operate in.

[–] Bishma@discuss.tchncs.de 4 points 1 day ago (1 children)

Virginia's exists because the navy was worried that a bridge accident or attack could cut off Norfolk Naval Station from the Atlantic. Submarines cross under the bridge though.

[–] IWW4@lemmy.zip 2 points 1 day ago

I always figured the Navy drove the decision making on that bridge. I haven’t driven over it in a long time but going over that bridge and seeing an aircraft carrier coming and going is so cool.

[–] Diddlydee@feddit.uk 26 points 2 days ago (1 children)

That's nothing. There's a magic farmer near me. His tractor turns into a field.

[–] toofpic@lemmy.world 14 points 1 day ago (1 children)

It's not like Denmark "preferred" a tunnel, it's just there is an island and waters are shallow, so they didn't need to go all-out "hammer supports in the sea"

[–] goldenbug@fedia.io 17 points 1 day ago (1 children)

IIRC the Island is artificial and the reason a tunnel was made was because the entry point would be too close to the airport, endangering the airport and the bridge.

[–] cosmicrookie@lemmy.world 15 points 1 day ago (1 children)
[–] toofpic@lemmy.world 1 points 1 day ago

Yes, I didn't say they didn't do anything, I only said "there's an island and the waters are shallow":)
But it's generally cheaper to dig and cover, thatn to build in the air.

[–] DudeImMacGyver@kbin.earth 12 points 1 day ago (1 children)
[–] belathus@lemmy.blahaj.zone 4 points 1 day ago (1 children)

They call the Virginia one a bridge-tunnel. The Chesapeake Bay Bridge-Tunnel.

[–] Valmond@lemmy.world 1 points 1 day ago

A schtrumpf - tunnel or a bridge - schtrumpf ?

[–] chillpanzee@lemmy.ml 6 points 1 day ago

I'm a little bummed it isn't called the Brunnel.

[–] WindyRebel@lemmy.world 1 points 1 day ago

Was this built to predict the rise in water levels from ice caps melting? I’m curious if that was engineered in as a potential issue or not.

[–] Onomatopoeia@lemmy.cafe 9 points 2 days ago

I do not think that word means what you think it means.

There's been a bridge/tunnel in Virginia since the 60's, crossing the mouth of the Chesapeake bay where it opens to the Atlantic.

I just woke up and I was staring at the thumbnail of the article for too long, waiting for it to be a gif of the bridge transforming

[–] BradleyUffner@lemmy.world 4 points 1 day ago

And then back in to a bridge again!

[–] Shirasho@lemmings.world 3 points 1 day ago

This sort of bridge is featured in the last level of every Ace Combat game.

[–] Hupf@feddit.org 0 points 1 day ago