A named region is contiguous (counterexample: The Australian Capital Territory, which includes a tiny coastline hundreds of km away).
It’s a border with multiple enclaves, it used to have a third-order enclave.
Ah, it becomes even more interesting when people go down to the country level and say that things are always like this. This includes funny things such a believing that certain things such as districts, towns, postal regions, streets, hamlets, states, etc. always have a similar relation to each other (one always fits in another) or that certain mappings are always really 1:1.
For example for postal regions mapping something like districts or cities in many countries, but as I had to find out that is only true for 99.9% of the cases, but even in capitals you sometimes have oddities such as one block being part of another postal region. Still people would swear this doesn’t exist.
I know that’s mostly address related and also linked in the article. It’s probably even more important for programmers, as it’s very likely to hit them when going close to something like customer addresses or geocoding.
I like reading Google’s Geocoding API for this. It just lists “Adminstrative Areas” 1, 2, 3, 4, 5 and lets you guess at what that might mean.
In the end that’s kind of what you have to do, also it might make sense as an API to not give you the impression it is hierarchical. I have seen in done pseudo-hierarchical and one shouldn’t underestimate the likelihood. Those things are way more common than one would guess on first sight. The main reason for writing this is that even when things are close to you it’s not known, even as a fun fact by people usually. So even when rules don’t always apply in your own city they might lead to wrong assumptions. And in that company there have been quite a few people how specialize in the field (Open Street Map people, real estate agents, etc.), still every once in a while got surprised by oddities in their own country/city. It mostly showed that individual postal offices carry a lot of probably not digitized or even written down knowledge.
It makes these things very interesting though.
Speaking about Google Geocodinh API I have another anecdote. There is a place in a German speaking country that has a Russian Cyrillic phrase in the middle of a shopping mall saying something like “bus station” I think and no, there is nothing related to it there. The closest bus station is however described correctly, so not sure what’s going on there. It’s a really fun find and it has been there for at least nearly a year (that’s when I found it), so nothing short lived either. It’s reported though.