Falsehoods programmers believe about geography

Gleis 9 in Zürich-Oerlikon (Switzerland) at the Oerlikon railway station moving to its new location

Computer science is a unique branch of engineering in the sense that programming by itself is not helping much. To actually write useful programs, one needs to understand what the programs are about. One of dangers of programming is having an erroneous model, and it is very easy to base a system on falsehoods. There are two very interesting posts about this on this subject on the web:

Here are some falsehoods about geography I found in software, the list is, by far, not exhaustive.

Places have only one official name
Some places have multiple languages, so multiple names, which can be quite different: Genève, Genf, Ginevra.
Places have only one official name per language
That might be true in an ultra-centralized state which never changes its mind. The hill behind my flat has two different names, depending on the maps. On the topographic maps (used by the army) the name is “Äntlisberg”, while on the city map, the name is “Entlisberg”, both are official. In Taipei, the romanized street names used to use different romanisation rules depending on the quarter, so the official street name changes.
Place names follow the character rules of the language
Place names are usually old, often created before the language and their rules have been stabilised, so this does not hold. For instance, the rule says in german the sequence “ue” is equivalent to “ü”. This rule works because the “üe” sound has died out in german. The hill over Zürich is named “Üetliberg” (and pronounced as such).

Place names can be written with the usual character set of a country
One of the Kergelen islands (part of France) is called Île de Croÿ, most french persons have no clue how to type the “ÿ” character.
Place names can be written with the exhaustive character set of a country
That would be true if streets where never named after foreigners with strange accents in their names. There is a Béla Bartók square in Paris. The “ó” is not valid in French.
Places have only one official address
There is a dam in Geneva that spans the Rhône and therefore the border. The dam has two street addresses, one in Switzerland, one in France.
Countries have capitals
Switzerland does not. The government is currently in Bern, but the city is not the capital.
Buildings do not move
In Zürich, a 6200 ton building was moved by 60 meters to make way for railway tracks
Street adresses contain street names
In many remote places in Europe, the hamlet name is considered a sufficient address.
Language codes will match the country code of the country they are associated with
The country code for Japan is jp, the language code is ja.

Edit: an interesting article about Falsehoods programmers believe about addresses.
Edit: Falsehoods programmers believe about online shopping…
Edit: Falsehoods programmers believe about text.

Gleis 9 in Zürich-Oerlikon (Switzerland) at the Oerlikon railway station moving to its new location – © Roland Fischer, Zürich (Switzerland) Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0).

63 thoughts on “Falsehoods programmers believe about geography”

  1. Moving buildings is definitely my favorite part. The first time you told me about, I was still very naive about Swiss ;-)

    • I have seen houses moved in the US. Mostly to a more convenient location. Sometimes they are built on a bad foundation but are nice houses. There’s an entire industry around moving them.

  2. I knew all of them except for Bern.
    Then again, I’m not a programmer (nor Swiss).

  3. “Street adresses contain street names”
    In Japan, the streets don’t even have a name. Buildings are referred to by block numbers.
    For instance, the address of Sony (HQ) is Tōkyō City, Minato ward, Kōnan district, 1-7-1.

    “Countries have capitals”
    Others have many. South Africa’s capitals are Pretoria, Bloemfontein and Cape Town.

    • “Tōkyō City, Minato ward, Kōnan district, 1-7-1”

      Tōkyō prefecture (state), Minato ward, Kōnan district, 1-7-1

      The former city of Tōkyō was dissolved in 1943. Some wards in the central area call themselves cities in English but of course not in Japanese. Other cities outside of the central area are still cities, including the one I live in.

  4. Programmers aren’t necessarily good at grammar, as evidenced by your first sentence…..G

  5. “Places have only one official address”

    This is even true within the same country. While the example given is a place with an address in two countries, in Switzerland (more Switzerland! :) there are bilingual cities/towns such as Biel/Bienne where every street has two different names (one French, one German) and therefore each location has two addresses. The street number and PLZ may be the same, but the street depends on which language you feel like using …

    • btw: PLZ is the German abbreviation for “postal code”.

    • Pretty much all addresses in Ireland (republic or NI) are bilingual and can be given in either English or Irish. In some cases, this also applies to the names of buildings. I believe that the same applies in Wales.


  6. – Countries are permanent.
    South Sudan was recently born. Netherland Antilles recently ceased to exist.
    – Your definition of a country will be the same as others.
    Is Taiwan a country? Kosovo? Puerto Rico?
    – Countries have well defined borders.
    Countries frequently dispute the location of their borders and the borders of other countries.
    – Taking into account disputes, countries have well defined borders.
    Treaties often define their borders in a way that makes it very difficult to figure out where it actually is. Borders are often defined by natural features that move (e.g. rivers).
    – It’s possible to render a single map of country borders that can be used anywhere in the world.
    Countries like China and India have laws that require maps in their country to render borders a certain way and those requirements are contradictory.
    – There exists some line you can use (disputed or otherwise) to mark the border between one country and another.
    Chile and Argentina have purposefully left a section of their border not surveyed and insist that that section not be drawn.
    – You can at least assume that areas within a country (states, provinces, etc.) have well defined borders.
    Borders defined by natural features (lake, river) often don’t specify where in the lake or river the border stands and what happens if the natural feature moves.
    – Countries are fully covered by administrative areas.
    – Administrative areas of the same level do not overlap.
    – Geographic divisions are contiguous or don’t have holes.
    – Names for administrative divisions have the same meaning in different countries.
    Nepal’s highest level of division is county while the US has counties as one of the smallest levels.
    – The administrative divisions within a country are consistent (i.e. all the top level divisions in the US are called States and those are divided by counties).
    The US has the District of Columbia and different states are divided differently. Many countries have “interesting” exceptions to their divisions, often around the capital (or largest) cities.
    – The administrative divisions of a country stay the same.
    – OK, the borders can change but the system/hierarchy stays the same.
    – Major changes in country divisions only happen every decade or so.
    – All the land in the world can be defined to be in some country.
    – Antarctica can just be treated as a separate country.
    Several countries have claimed overlapping portions of Antarctica.
    – Postal codes are geographic features.
    Businesses love to assume that the world can be mapped by postal codes. They base many decisions around this and by the time they find out it doesn’t work they don’t care and insist that it work anyway. In fact, postal codes are almost never defined geographically but rather just consist of a set of addresses that fall within the given code. So it is technically meaningless to say that a point falls within a given postal code.
    – A postal code can be used to refer to a city.
    It is often the case that a postal code covers a city and a giant portion of neighboring rural land. This means that searching for a mechanic in your zip code can easily get you a result many many miles away.
    – There is an official definition for the international date line.
    – The date line doesn’t change.

    • To add onto your addition to the original article:
      – Lat/Long is sufficient to uniquely identify a location. (You need elevation too)
      Especially in water, a buoy at Lat/Long is going to be in a very different place than a camera in a trench at the same lat/long. Even on land, caves/tunnels/canyons can mean two places with the same lat/long are separated by hundreds or thousands of feet and are moving between the two points requires a very roundabout route.

      • Simpler examples are overpasses, tunnels, and bridges. Some systems will route a driver to a tunnel under a business, which will take them far away from their intended destination. It’s also not sufficient to just not route to the tunnel or bridge because in many places the destination is on the bridge or in the tunnel.

    • Each state has its own smallest administrative unit. Almost every state has precincts or wards within counties. (Useful for vote polling places.) The US Census groups areas by “census blocks” which you can get data for if you’re looking at demographics. These have nothing to do with the state designations for precincts or wards.

      Louisiana is special in many ways, since they kept a lot of the old French ways. They don’t have counties, they have parishes, for example.

      In Virginia, you cannot be in a city and a county at the same time. Cities are their own, parallel administrative unit and counties only encompass unincorporated areas.

      Most of the states west of the Mississippi have more standardized rules since several of the western territories were divided up into counties when states were constructed, based on lat./long. definitions for plats that were defined for formation of various political divisions. But I live in a city which shares borders with it’s parent county in California which has a lot of historical blurriness based on how the city was a city long before it was ceded to the US.

      There is a tremendous amount of history in the definition of place. I can only imagine it’s significantly more complicated in a location that has more (accepted, recorded) history.

  7. I grew upon a small island of the west coast of Ireland (pop. ~600) where my mother was post mistress. We regularly got mail addressed to some one on the Island with no other information. Because there are very common traditional names in use on the Island there may have been ten or more individuals sharing a name. A guessing game would ensue to try and identify the correct recipient (clues would be origin of letter, handwriting, asking P.O. customers etc).

  8. * Administrative divisions are always used in postal addresses
    * A level of division will never be created or removed from use

    Finland used to be divided into six provinces, purely for political and administrative reasons. A lot of foreign sites treat these like US states and include them in postal addresses. The system was abolished in 2010, but province selection still haunts many sites.

    This is also a great way of spotting bots and spam. No live human being would say “Are you also from Etelä-Suomen lääni?”

  9. 地理 in computation is complicated.

    I had to adjust a form for ordering a small set of products for multiple countries a few years ago. Although all these countries were European (most from the Eastern hemisphere) there were still plenty of differences among them. Some form fields had to be added/removed due to administrative differences, some of them because of legal issues.

  10. In Northern Ireland, there’s a city called Derry or Londonderry, depending on on which side of the Republican/Loyalist divide you stand. It’s a very sensitive topic, so that the BBC uses the phrase Derry/Londonderry.

  11. “Places have only one official name per language” – for example, in Central Europe, place names change. A lot; depending on who’s currently in charge. There’s a square in Prague which, in the past 100 years, has had about 6 different official names (sometimes as many as 3 changes within 10 years, good luck with “just keep the current name and the one immediately prior to it”).

  12. Some countries have more than one capital city (South Africa), and some countries have a capital city that is not the seat of government (The Netherlands)

  13. In 1999, a lighthouse in Cape Hatteras North Carolina (USA) was moved 460 meters (1500 feet) due to shore erosion.

  14. – A given point on the ground has a definite latitude and longitude.
    The Earth’s surface can be approximated by any of a vast number of ellipsoids. Interpreting data in one as being in another can throw a position off by hundreds of metres.

  15. There was a nice Foursquare bug when Curiosity rover made its check-ins on Mars using Martian latitudes and longitudes but the maps showed places on Earth. So, another falsehood might be: all coordinates belong to Earth.

  16. Another: Every address has a ZIP Code. Addresses in Ireland has NOT.

  17. There’s Aÿ in continental France, famously mentioned in Alexander Blok’s poem “In a Restaurant”: “Я послал тебе чёрную розу в бокале // Золотого, как нёбо, аи.” (I sent you a black rose in a glass of golden like the palate aÿ [i.e. champagne]).

    In Albania, all nouns, including place names, have an indefinite and a definite form, e.g. Tiranë and Tirana.

    In Poland, postal codes follow the administrative divisions from 1973, revamped twice since then.

  18. – Both sides of a street have the same street name that spans the whole lenght of the street.

    Mannheim city center (germany) has, like New York, a rectangular street grid, But: The do not name the Streets, they name the blocks (with a combinations of Letters in the North-South axis and numbers on the east-west-axis) and then count house numbers counter-clockwise. So if you walk down a street, the houses on the left side will have addresses “M5, 6”, “M5, 7” while the houses on the right side have adresses “N5, 9”, “N5, 8”. If you walk further down the street, right after the next crossing, you are standing between “M6, 1” and “N6, 12”

  19. – That countries other than the U.S. exist and that they have states.

    I get tired of trying to enter my address, selecting my country (“New Zealand”), and then setting my state to “Alabama” because the form demands you choose a state – which we don’t have.

  20. When the government of a country declares a new set of boundaries for administrative areas, everyone will start using them.
    (Counties in the UK are defined historically, then the government plays around with administrative areas, confusingly given the same names but with different boundaries, meanwhile the post office adopts a third set of boundaries. You can stand in Bournemouth, and claim to be in either Hampshire or Dorset, depending on your views.)

  21. As someone that orders pizza delivery on a regular basis…

    Falsehood: The apartment number will be sufficient for locating the residence once in the apartment complex.

    It’s perhaps a related item to “places do not move” in the fact that “Addresses never change once assigned” because the “driveway” was upgraded to a “public road” the city took over when further development happened in the area, so suddenly the apartment complex got assigned fixed street addresses for all the structures instead of only one for the whole complex, but wasn’t allowed to change the registered apartment numbers.

  22. “There’s nothing interesting at [0,0], you can use that as a null value” and its counterpart “if something has coordinates [0,0], treat it as if it is physically located on top of the ATLAS buoy in the Gulf of Guinea”

  23. Another one, although partly addressed already, would be that placenames don’t start with a quotation mark.

    ‘s-Hertogenbosch is a large city in The Netherlands. I’d imagine some systems having trouble with it.

    • And another falsehood is that “smart” curly quote algorithms always get it right. In particular, initial apostrophes tend to use the same character as a closing single quote, so they frequently get this wrong.

      In this case, I believe it’s ’s-Hertogenbosch, not ‘s- as you had.

  24. Only one capital city.
    Bolivia has two: Sucre and La Paz. This changed along its history.

    Capital city doesn’t change.
    Argentina had plans (and laws) to change capital from one city to another, but the plan was later discarded.
    Brazil changed three times: Salvador de Bahía, then Río de Janeiro, currently Brasilia.

    Only one name for a city.
    The (current) capital of Argentina is variously named “Buenos Aires”, “Ciudad de Buenos Aires”, “Ciudad Autónoma de Buenos Aires”, its acronym “CABA”, and “Capital Federal”. You may see any of these in web forms and in addresses (e.g. envelopes). There is also a province (state) called “Buenos Aires”, so things can get confusing. The city and the province share border and are disjoint.
    Also, in Argentina some cities have a short name in common use and a long official one: Tucumán (San Miguel de Tucumán), Catamarca (San Fernando del Valle de Catamarca), etc.

    Only one name for a country.
    Similar to cities, some countries have a short name in common use and a long official one: Bolivia (Estado Plurinacional de Bolivia), Venezuela (República Bolivariana de Venezuela), etc.

    You can know from the name if it’s a city or a province/state.
    In Argentina many provinces and their capitals are called the same: Córdoba, Mendoza, San Luis, San Juan, La Rioja, …

  25. Falsehood: national boundaries are defined only in space, not in time (Pheasant Island belongs to France for six months of each year, and to Spain for the rest).

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