Are these even legal in Europe (the part that is not the UK…)?

And perhaps you can convince them to at least let the earthlings hear some lyics before the destruction!

Don’t know if this fits with what you want to get at, but the main part of the rear mudguard for my mountainbike has now been the cut-up bottom of a 1.5l plastic bottle, fixed with zip-ties to the end of the bike, for many years.

Not only is it superior in function to all the expensive commercial variants I used up to now (actually has a suitable shape and size to catch all the mud…), but it surprisingly also seems to be more durable. And also lighter.

Optics are… special… though.
But I really see that as a positive point: The more ugly a bike appears, the less likely it will get stolen.
Besides, it is a nice talking point when meeting new people :-)

These are actually really interesting examples.

Take Iran:

On the one hand the area where it is located has had organized societies occupying it for an insanely long time.
This would make it one of the oldest countries by this definition.

On the other hand: when asked the question if the current Iran was the same country as back in the 1970’s, I would certainly say: “No.”
Occupied area and even some of the people might still be the same, but the cultural, societal and governmental characteristics have changed too radically to still be considered the same.
So, by this definition, Iran would be one of the youngest countries.

I think that uncertainty is what OP was getting at:
How much change do we allow to still consider a country the same as at a previous time in history?

Really relies on what you define as a “country”, and how those definitions might have changed across time, or might not even have existed at all.
The US is probably one of the easiest ones.

Enter Europe:
Has the German Reich been a country?
Then what about the Grand Duchy of Luxembourg, which today is undoubtetly a country but has also been a part of the German Reich, following its king?

Similar for other claims of age.
We have e.g. 3 “oldest” cities in my country, each relying on a slightly different definition of “city”.

Survival of the fittest.

Yes, 2/3 of the wooden cutting boards I put in became unusable after a few washes or so.

But totally worth it finding that remaining 1/3 of tough ones that are now making life sooo much easier.