[lugao]

It's funny because you can't measure borders due to the coastline paradox.

[falcor84]

I'm not aware of any 2 countries having their border be a natural coastline

[retsibsi]

Same principle applies to rivers, though, and there are lots of river borders.

[wolvesechoes]

Doesn't matter in this context.

[jcattle]

Eh. If you care about relative measurements it doesn't matter much. Pick a sensible resolution, stick with it, you got yourself a ranking.

[heavenlyblue]

It also makes sense to pick a resolution because coastline changes on an hourly basis (and minute-basis, for rivers during rainfall), so that these differences would not massively affect the measurement every single second