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I did a bunch of analysis of UK addresses at a former job. My favourite was the clear inverse correlation between house number and value, with a noticeable dip for number 13s, which from memory were valued around 2.5% lower than where they should have been.
I live in an Edwardian street and my house should have been 13 except it isn’t. They skipped it and my house is 15 instead. Hopefully the universe doesn’t spot this deceit!
Perhaps the story is that there is some bias in the streets which have number 13s instead of skipping like on your street and that’s the reason for the price difference?
Now I’m curious about the ratio of houses numbered 13 and 12a (then 14 with no 13) across the UK.
Generally, we have odd on one side and even on the other, so this isn't likely.

The odds and evens are usually also allocated sequentially and independently, so it can be incredibly annoying when you're looking at the numbers on the wrong side of the road thinking you're getting close when you're actually walking away from the house because the numbers are much higher or lower on the other side.

Some UK streets don't have a #13, i believe because 13 is widely considered unlucky
Yes I lived in such a street, 1at number 11. 1960s street.
Yes, there was a noticeable drop in the count of number 13s too.
One "weird numbering scheme" according to the article is setting house numbers based on distance (in meters) from a predefined "street start" point.

I find this arrangement to be the most convenient one, and I've found it quite often in villages in France.

No need for "bis" or "3a" or "3 ½" house numbers, and a consistent method to obtain the position of a house based on its house number.

Yes especially in rural areas, where houses are sparsely spaced. If 15 and 17 are 3km apart, you can have several hundreds houses appearing between these numbers, and no amount of "bis" and "ter" will save you.
I believe they do that in at least some areas of New Zealand.
They do indeed - it’s called RAPID (Rural Address Property IDtification) and is used in most rural areas. For instance a house 5.5 km down a road on the left will be 501. Makes it very easy to find places, all you need is a working odometer.
Also avoids oddities when multiple buildings are build between existing ones at some later point. As there is usually plenty of space to add them.
This is increasingly how exits are numbered on highways in the USA Interstate system. So exit 52 is about 52 miles from the start of the highway or the state border. It works well because exits are rarely spaced close together. And if they do need to put exits close together, usually they letter suffixes like 52A.
Here in Vermont, we're half-assing that conversion: the canonical exit number is sequential, but below the sign at the exit you have something like "Milepoint Exit 38". It drives me nuts.

Another truly perverse thing is that if you're on I-91, the exits for I-89 have numbers (10 A and B). On the other hand, if you're on I-89, there are no exit numbers for the I-91 exits. What? How?!

IIRC I89 exits are numbered starting from 1 at the border with NH which happens to be just east of that interchange. Maybe adding a number for I91 would have forced them to renumber every other exit across the state and someone decided (for better or worse) to skip that? It’s not as if the I89 exit numbers would line up with the I91 ones anyway, that would be even less sensible.
You do recall correctly and it seems like this would be yet another excellent reason to just renumber all of the exits by mileage. Wikipedia doesn't quite answer the question of which road was built first where they meet.
Isn’t this a standard in parts of North America too? Although probably using feet instead of metres.
I think that this is usually implemented as a thousand numbers to the mile.
From the small number of US cities I've been to, it seems to be 100 numbers per block and roughly divided up between whatever's there. Sometimes evenly spaced, sometimes starting from 1 at one end at 99 at the other and a free for all in the middle.
Many addresses in slightly-more-rural Australia work like this. The road I grew up on was numbered by the 10s of metres from the main road. 192 was 1.92 KM from the main road.
It is indeed used quite a lot in France, and it's great but... For extra confusion my parent's street starts with straight numbers (1, 2, 3...), _then_ switches to distance-based count! So that on one side of the road, we get houses 43, 45, 47, then suddenly 947, and on the other side 64, 66, 68... then 920.
In rural Finland you'll often see 100 house numbers per kilometer. Alternating even & odd, you'd get a number every 20 meters, which is more than sufficient. I'd think this is really handy for emergency services, when people don't bother to put up house numbers on dirt roads.
In some rural parts of the US the only numbers you’ll see are little red signs for emergency crews.
In France, I believe that distance from town hall is used to pick which end of a street is to be no. 1. But then numbers incrementally follow from there.

Distance is not used to rank each property.

In built-up areas, the numbering is typically sequential. In rural areas, houses are numbered based on distance from the start of the road.

Our road in the _campagne_ has two houses: number 50 (50m from the start of the road) and number 70 (at 70m).

Another UK Postcode oddity is Gibraltar which has GX111AA as the postcode for the entire country
A lot of the British Overseas territories have adopted similar postcodes (e.g. ASCN 1ZZ for Ascension Island)

Although it’s disputable whether they are a part of the UK, or separate administrations that have postcodes designed to look like a UK postcode!

I don't know if that is so odd to me. Gibraltar is 6.8 sq km. The post code where I have grown up in east-europe is roughly 7 sq km. So to me that makes perfect sense as a post code.

Is there a rule on how big a post code is supposed to be?

(Now, my current postcode in the UK is just the single house. That for example feels way too small to me.)

UK postcodes are usually _extremely_ specific. One postcode per road or even block is very normal.
Even more so. Some buildings I lived in had several postcodes. (e.g. some apartments in the building had one postcode assigned, and others had a different one)
[According to Wikipedia] the aim is to have one post-code per fifteen addresses.

Which means that unlike (5 digit) ZIP codes and German Postal codes, UK Postcodes are typically pretty useful for navigation - people will often enter a postcode into a Sat-Nav to reach a home or business. However, sometimes this can entirely fail - e.g. for a historic house on a large estate which may have access some hundreds of meters away from the postcode indicated location, and so sometimes you'll see a separate postcode to put into your Sat-Nav !

Gibraltar is not a country
A very extreme variant of this is Hong Kong, a country of over 7 million people, which the Chinese postal service allocates _one_ postcode to. (AIUI this postcode isn't widely used outside of China).
Most of the time in HK the postcode of "0" or "00000" is used when a zip code is required
> the entire country

City/overseas territory*

I live at flat 8 of building 5, which through a strange quirk in the way addresses are created in my city & then recorded at the post office, accepts mail intended for both 8/5 and 5/8. A nearby neighbour in flat 5 of building 8 also receives mail intended for both 5/8 and 8/5. Most mail providers automatically adjust "flat 5 building 8, street name" to "5/8, street name", so we've got no way of fixing it.

Everyone in the estate who lives in flat 9 or lower in their respective buildings has the same issue, and the issue also occurs in a bunch of other new builds in the city.

I have a friend who lives in a house which was knocked through from two houses. She has two addresses, either work. She also has two gas meters, two electric meters and so on, although she got those disconnected (to save on standing charges).
Exact same situation — except my structure was 100+ years old and also had Yet Another Address for utilities (from century-old infrastructure).
Yes, I had the same issue previously. It was constant mixing between flat 1 building 2, vs flat 2 building 1 (2/1 vs 1/2). I think trying to be explicit 'Flat N, M X street' helps instead of using the A/B notation. (although now I leave in 7/7 so I don't care).
I lived in a flat where the convention was to write the flat number like 8/5 and would occasionally get mail to the equivalent of 08-May.
They should combine this the street numbering/naming scheme seen in some western US states (notably Utah). Not hard to imagine the old US "10th St." followed by "11th St." etc. But in some towns, you get "10-1/2 St". I think I may even have seen "10.5th St" and maybe even "10-1/4 St". Someone explained this to me as a rational way to reference canonical "block size" but I'm unconvinced.
There are a few areas in L.A. where between 137th St. and 138th St. you will find the much smaller 137th Pl.
I lived in a big tower in London a year ago and during my stay there my postcode changed twice. Many systems, for example Credit Checking agencies, etc very much do not like this and it's such a pain to deal with.

It got a new postcode because there were too many delivery points for my initial assigned postcode so they split it. Twice.

The underlying system behind this is Royal Mails augmentation of the UPRN system with the UDPRN (Unique delivery point reference number) which is meant to be 1:1. There is then a further classification for multitenant units called the UMPRN (unique multiple residence number)
One of the interesting things about UK addresses is the Royal Mail issues an official list of all the addresses they know of - the "PAF" - as part of their work assigning postcodes to buildings.

That means in the UK it's possible to almost definitively identify, for example, the longest address.

Whereas in other countries that question is unanswerable, because who's to say whether a given building's address is "32 Vassar St, Cambridge MA" or whether it's "Massachusetts Institute of Technology Computer Science & Artificial Intelligence Laboratory, 32 Vassar St, Cambridge MA" ?

Also incredibly useful is UPRN and USRN for properties and streets. Almost* every property has a unique identifier which is portable across systems.

*I believe the top of the funnel for the UPRN process is council tax registration which not all buildings need

Yep, the reason I hedged my statement, saying "almost definitively identify", is that, as you say, some buildings aren't listed.

For example some village halls aren't listed in PAF - perhaps because they can't receive mail? And structures like electrical transformers aren't listed (even when they're built of brick and on their own separate plot of land).

New build properties supposedly appear in the PAF before construction is completed - but that depends on both the builder, and the PAF user getting the latest updates.

PAF isn't strictly a list of addresses in the sense anybody other than the Post Office (and maybe parcel delivery firms) would care about.

PAF is a list of delivery points to which they can deliver mail. So for example the place I work isn't listed, you can't deliver mail to it even though it's a large building with multiple entrances and you'd obviously be able to direct people here specifically, but mail "for us" goes to some admin building several minutes walk away across campus.

>I believe the top of the funnel for the UPRN process is council tax registration which not all buildings need

UPRNs are issued for structures that aren't houses or even buildings.

10010457355 is Stonehenge, for example, and 10022990231 is the Angel of the North.

Indeed - there are even UPRNs for bus stops, defibrillators, and post boxes.

I have also seen lamp posts, EV chargers and fibre infrastructure street cabinets receive them. No need to be a house or building!

One of the depressing things about UK addresses is that this list isn't open data.
And some of the usable (still not open) files exclude Northern Ireland so it's GB not UK data really.
Energy performance certificates are open though https://epc.opendatacommunities.org/ which includes address and, in some cases UPRN (unique property reference number)

It's also a pretty interesting dataset to explore

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I think you're mixing up separate concepts. The USPS has a fully normalized format for all deliverable addresses. Anything above that is purely for the convenience of the recipient.

32 VASSAR ST

CAMBRIDGE MA 02139-4309

https://tools.usps.com/zip-code-lookup.htm?byaddress

Yeah, this confused me, too. Do they not put names on envelopes in England?
I don't think we have to. Mail can be sent with just a postcode and door number, or just a postcode of the place is v something big.
Names are optional here, too, though I think you'd have a harder time with just a code and door number. The full address is number, street, city, state, zip.
there's probably exceptions but a postcode should resolve to a specific building, street or part of a street so it would work in the literal sense but it's more work for the people delivering the mail I guess.
The article linked here mentions at least one road which appears twice in the same postcode and has confounding numbers.
>Mail can be sent with just a postcode and door number

Oh, good grief. From this very article:

>The widely stated ‘fact’ that all you need to provide is a house number and postcode for your post to reach the right address is not always true. There are many instances of different buildings having the same number and postcode.

The phrase "Mail can be sent with" is ambiguous. "can always be sent"? no.

But, if read as "Mail can (often, usually, generally) be sent with just a postcode and door number" then it's perfectly true of the UK. And that's a great achievement. I've seen far worse postcode systems.

Real world naming always has special cases, so no surprise there. This doesn't entirely invalidate the general point.

The recipient might need the name if more than one person is resident. But the post delivers mail to addresses not people. I did once encounter the postman as he was walking from the road to my front door. I asked him to give me the post as I was on my way out but he insisted that it had to be delivered to the house not to me.
> You might assume that the lowest house number would be 1, but there are quite a few houses numbered zero.

In Richmond, VA, there is a historic building which at present is owned by the Black History Museum. It is 00 Clay Street. That's two zeros. It's the coolest address I know of.

https://www.nps.gov/places/00-clay-street.htm

This one is confusing because it’s on the odd side of the street - 00 is clearly acting as minus 1.
No, the house on to the left is 1 East Clay street, and the house on the right is 1 West Clay Street. Directly across from 00 Clay Street is a street. On either side of that street are 2 East and 2 West respectively. 00 is the only house not on East nor West Clay Street, but just Clay Street. It's at the origin.
This is a better explanation of it. Thanks!
My parents house was built before development of the area. The original road was built on and another road built on the other side of the house, both the old and current street names are still valid postal streets (the old street name is still attached to the house on the end). The old street name is commonly used to refer to the terrace of houses. My parents still have legal right of access (recorded on the deeds) across the back gardens of the houses that were built on top of the old road.
I love the old rights of access, I really do, war houses in the UK were built for a vastly different way of living with your neighbours.

I live in a terrace, and four of us share a ginnel that my house sits over, splitting the terrace into a 2/2 on the ground, and fully attached 4 above.

My ‘ground attached’ neighbour is great, shares it no problem and has full access to my garden. The neighbour on the other side of the ginnel has blocked access for her ‘ground attached’ neighbour by building a greenhouse infront of the gate, so she must store her bins on the street rather than her back garden and be deprived of the ability to wash her car, get a window cleaner for her rear windows etc.

That's why geocoding is HARD. Try "3 Adne Edle Street, London" on Bing maps, Google Maps, Openstreetmap, Geocode.xyz - and more.

Or even better, try "Minus Two, Woodend Lane, Cam, Stroud"

No two geocoding services agree on the correct answer.

>Or why a house in Owls Green, a village of about 20 houses near Ipswich, would be numbered 2820 (cute).

For those who aren't native British/English-speaking, this is presumably a cute reference to the village's name of *Owls* Green, since at least in the UK the onomatopoeia for one of an owl's sounds is "too-wit too-woo", to which "two-eight two-oh" is similar sounding.

Ah... I didn't get it. I even put the number into Wolfram Alpha to see if it had a nice factorisation or something.
A moderately tangential weird fact...

"too-wit too-woo" sort of isn't the sound of an owl... it's the sound of two tawny owls, it's a female call (the 'too-wit' bit) followed by a male response! :)

(Ref: https://www.wildlifetrusts.org/wildlife-explorer/birds/birds... )

I'd like to know where the one near Beccles is. I used to live there and I'm quite surprised to hear of such an amusing hack nearby. Curious that the other high number one is also in Suffolk, only about 30km away.

Now I'm wondering if it's possible to register an irrational number like Pi. I suppose "Pi" could be a house name but I would want it to be the number.

It's a string so you can probably register anything you like. In our village there are is a road with houses with numbers "<N> Cottages" and "<N>" (for various numbers <N>). I guess post is often misdirected.
Some people like having house names as well as a numbers. We live at no.69 and I once entertained the idea of calling it "No. 47", but the idea was quickly vetoed.

(In case you're wondering "why 47?", for some reason our street doesn't have a no.47, so it would have been a fairly benign joke)

Yes, as a Suffolk resident I'm wondering if there's some special thing about high house numbers.
I grew up maybe 300m from the Minus One house mentioned in Clacton On Sea and did a paper in that area for a couple of years and never heard of it so I’m wondering how true some of these really are?
Well, you can read it ("MINUS ONE") on the front of the house if you zoom in on the StreetView photo. And the Royal Mail recognises it (try pasting "minus one, clacton" into https://www.royalmail.com/find-a-postcode).

Though it may be a house name rather than a number.

Yeh I think it’s a name rather than a number to be honest, also I’m going back twenty years so might not have been a thing back then.
When I was living in Edinburgh, I encountered the corner case of the upper levels of an apartment building having a different postcode from the lower levels. Everything online used the same address database so I wondered why I could never find my address under my (presumed) postcode.
Edinburgh is awesome, in particular, for the way that flats can be numbered within buildings.

I used to live in flat on the top floor which received mail as either "TFL" (for top-floor, flat on the left", or "Flat 6". Different companies used different formats for the address.

I'd lived in GFL "ground-floor, flat left" and "GFR" for "Ground-floor, flat-right" as well. But never in a middle floor. I assume they would be MFL and MFR respectively. But who knows?

when i lived in edinburgh in the 70s, we would just stick a card on the flat door with the surnames of the inhabitants on it - the flats themselves did not have numbers.
That is pretty much how it works in Germany - flats are identified by resident surname, and numbers, if they exist, are not known or little used.
Norwegian apartments are all identified by a single letter and four numbers. For example, H0203 means 2nd floor, 3rd apartment from the left as seen when ascending the stairs. The H means "main floors" (as opposed to the loft or cellar). Very useful when visiting other apartments.
They use 1FL/1FR for first floor, 2FL/2FR for second floor, etc.
Flats on floors in between usually have the floor number as the first part: "3FL" for third floor on the left or "2F3" for second floor, third flat. Or at least that's how it was when I lived in Edinburgh in the 90s.
My flat in Edinburgh has two official post codes, depending on who is communicating with me.
When I worked at Scottish Gas, dealing with tenement flats in Edinburgh was always a nightmare because TGB (the old billing system) used the old 1F/2F/3F system but the electricity system used the numbered system - so customers would get mail for both but it would be mixed up all the time.

If you have to deal with a pre-pay meter going in, or just a change in meter they usually screwed up the MPR number with the address and end up replacing the wrong one.

And I lived in Edinburgh for 13 years, mostly in tenement flats - so it was always a hassle.

I've seen this done (in England) for blocks of flats where each floor has it's own postcode that matches the floor, eg ZZ1 Z1A through to ZZ1 Z1G (A-G for floor 1 to 7).
I don't know how many streets named "Letsby Avenue" there are in the UK; but apparently there are at least three different police stations on such streets.

NOTE: "Let's be having you" is a cliche Dixon-of-Dock-Green-style exhortation from a policeman to a villain, urging him to give himself up; c.f. "It's a fair cop, guv".

"Let's be 'avin you" is much better known as a football rallying cry, isn't it? I'd never heard of it as a police thing.

The most famous example of the phrase I'm aware of is when Delia Smith, a septuagenarian TV cook, exhalted her home Norwich City fans with a drunken slurred voice at half time over the PA system.

Not sure why I've been downvoted! Here's the video. Every football fan in England will connect the phrase with this event. It's not a bad thing, she's a national treasure.

https://m.youtube.com/watch?v=NiC679ASOyA

I think you are downvoted for not quite being correct. I think "Let's be 'avin you" is by far better known as a police thing.

This is what made the spectacle of a drunken Delia shouting it at a crowd all the more absurd.

I was asking a question, so it's a little unfair for people to have downvoted me without answering my question.

I think it must be an age thing? I've never heard of Dixon of Dock Green (born late 80s/early 90s). If I asked anyone I know how they connect that phrase, it'd be Delia.

Anyway, thanks for engaging.

I was born early 80s

I never saw Dixon either, but the phrase seems pretty common and well known.

The downvote thing is annoying...it would be nicer if people just replied

A very popular joke in kids' joke books in the 80s.

Q: Where does a policeman live?

A: 999 Letsby Avenue.

999, of course, being the UK's emergency number.

How are house numbers allocated on El Camino Real in California? (AKA El Camino BIGNUM) I believe they run to 5 digits; Does every house-number have a house?
And can you address houses one block over by specifying El Camino Imaginary?
Wouldn’t that be a road that’s perpendicular to El Camino Real?
I think it'd go straight up.
5 digit house numbers are pretty common throughout California, partly because in general, house numbers will start a new group of 100 each block, making it a lot easier to identify in which part of town a given address falls. So a given block will have numbers 102XX, the next block will have 103XX, and so on, even though the 102XX block may only have numbers 10200-10241, for example.

What’s even cooler is that, in L.A. at least, block numbers are assigned so as to “sync” with each other; the 9800 block of Sepulveda is due exactly west of the 9800 block of La Cienega. And, cooler still, the 9800 block of both streets (actually, pretty much any north-south street) will be between 98th and 99th streets.

The address numbering system in L.A. is surprisingly effective and consistent for a town that is essentially a patchwork of dozens of independent cities, with a mountain running through the middle of it to boot.

One other oddity is that there are "magic" postcodes in the UK that map to various government services, for instance:

BX5 5BD

Is a postcode to use when sending mail to HMRC(the UK tax office), but that address doesn't exist anywhere if you try searching for it. Royal Mail is the only company that can deliver post to that address too, they have the internal mapping to know where it needs to go - no other courier company will accept letters to that address. And, annoyingly - Royal Mail's own online postage store doesn't accept it as a valid address, you have to buy stamps and hand-write the address.

I don’t think that’s true about only Royal Mail can post there. There’s clear instructions on gov.uk for all couriers on where to send the mail if they come across this post code, it’s not some weird secret.

https://www.gov.uk/government/organisations/hm-revenue-custo...

Yes, but you can't use the BX5 5BD postcode if you do. They give you an alternative address for couriers.
One oddity not mentioned here that I came across recently, (which probably would go into one of those "things programmers don't know about postcodes" blog posts).

A system that used Postcodes for geocoding (not a great idea) was choking on PO Box codes that belong to districts (such as W1A in the London W district), but don't really correspond to actual street addresses.

This also catches some people out who will unintentionally use the PO Box postcode alongside the full street address of a business for example.

I've also worked on the TV Licensing systems (yes, the one that sends you scary letters every year). That has its own database of postcodes and addresses and I got to spend lots of time on the funny rules there.

>That has its own database of postcodes and addresses and I got to spend lots of time on the funny rules there.

How come the separate database vs the Postcode Address File? Sounds like you could write an interesting "Things programmers mistakenly believe about UK addresses" post very easily :-)

The postcode address file is for places you can deliver mail, whereas TV licensing is interested in places that might have a TV. There must be some cases where there's no overlap.
I started writing a reply saying I couldn't imagine such a place (and that I assumed it was about dodging the Post Office's license fee), but it looks like you're right - in researching the reply I found an article[1] from back in 2006 stating that at that time in England only 60% of buildings had entries in the postcode file!

They cite the example of churches that don't receive post, I guess if somebody had a TV there & used it to watch live broadcast TV then the building would need a TV license. I do wonder when the TV Licensing door knockers would show up trying to gain entry... during a church service seems a little inappropriate!

1: https://www.theguardian.com/technology/2006/jul/13/epublic.g...

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The most brainfuckery'd UK address oddity I've encountered is a road in North Manchester which has the same house number twice on the same road in the same settlement. In other words, there's two houses legitimately called something like "280 Manchester Road, Frogstall".

This is because the village is split between two borough councils, and each started from 1 when numbering their street. So one of them is "280 Manchester Road, Frogstall, Rochdale, Greater Manchester" and the other is "280 Manchester Road, Frogstall, Oldham, Greater Manchester".

Exasperatingly I can't find the exact address again.

I used to live on a street like this in Seattle: three blocks from its northern end, the numbering scheme resets and begins counting back up. Seven houses in the northern section therefore share their numbers with houses twelve blocks south. Mine was not one of them, but I got many calls from confused delivery drivers all the same, looking on the wrong section of the street for my seemingly-nonexistent house.
In Boston (Massachusetts USA) there are two different 24 School Streets, the other one is in a community that were annexed by Boston, so you'd say 24 School St Jamaica Plain but saying "Boston" isn't wrong either. For a long time Google Maps for some reason didn't store the zip code when you put this as your work address and would simply choose whichever one was closest to the destination.
Related but not exactly the same - there are a few streets that have duplicate numbers close to each other because they run from a point in Cambridge to one in Somerville, and both cities number up from 1 at their end of the street. I can’t find an example though…
I just moved away from a similar situation in SE Tennessee: multiple properties share "the same address" along the same road because this state highway passes through a city, then county, then a different city.

My former property (a duplex) had the same repeat addresses as a financial advisor, health spa, and post office. Many people showed up over the years, looking for such services from a decrepit 100 year old cabin located miles away from their intended destination.

--

When I attempted to resolve this numbering issue, the postmaster made it very clear that people would fight this (and did). After eight years, I recently moved away [and nothing has been resolved].

I once had to meet in person in with someone and they chose a town in France near our common objective. The town happened to be sitting across a departement line and had two town halls, each of which oversaw half of the town. Guess where we were supposed to meet in a time before cell phones.
These are all quite fun oddities. The one about house number and post code being insufficient is reasonably obvious if you’ve lived in a village in the uk where it’s pretty common for houses to not have numbers (only names like ‘the old school house’) and later be split up into two semi-detached houses hence getting separate numbers leaving the village with lots of number 1 or 2 houses.

So far I’ve already lived in places where a number+postcode were insufficient, where one building had multiple postcodes, on a one-word street, and I worked at an ‘& a half’ address. The street number thing I’ve noticed is mostly that as buildings have grown since the numberings were introduced, they became much less sequential so you see a lot more round numbers – buildings would rather be number 20 than 19 (and they’d really like to be number one), for example.

I'm glad that in Germany it's not as weird as in the UK then... we only sometimes have postal issues on newly zoned areas.
Despite the oddities it is actually quite nice in practice.

Almost all websites are hooked into this so filling out an address is usually just type in your postcode & select your flat number from the list.

I don't know if they still do it, but a cousin of mine in England in the 80s lived in a house with no number. It was simply "The Woodlands" in that particular village.
Yeah this is very common in the UK for a house to have a name rather than number, particularly in old villages.
This reminds me of the "What is the minimal possible UK address?" post from earlier this year

https://news.ycombinator.com/item?id=34995370

It's more "minimalising UK postal addresses" IMO, but still good.

"No.10" I think would be a pretty good answer for shortest address most likely to arrive at a specific building. You might get away with "#10"?

Although, post for Number 10, Downing Street, might be actually processed elsewhere; so maybe it's a fail.

I've been in London for over ten years, and family back in Portugal still struggles with the idea that

    Flat <number>
    <Post code>
    UK
is enough to uniquely identify my address.
I grew up in London, in a house that shared a postcode with only one other house.

A school friend didn't believe I would successfully receive mail addressed with only my forename and postcode.

(Until he tried it and I brought the received letter to school.)

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In Singapore, six-digit postcodes uniquely identify individual buildings. If your recipients happens to live in a single-occupancy house (quite the luxury in high-rise Singapore, it must be said), you could address mail simply as:

  Singapore 123456
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