So for example take the french-german frontline, my question is about the triple point where that frontline intersects with switzerland.
What stopped the soldiers from flanking through the neutral country, sure its technically a declaration of war to the neutral country but what stopped soldiers from doing it anyways? Also, were borders defined clearly enough for people to even know where one country ends and another starts?
Did the trenches just stop all of a sudden and both sides "agreed" to not go any further? Did neutral nations have to station their own soldiers at the border to enforce their neutrality? If so, were those soldiers effecticely sitting there, watching the others fight it out a few 100 meters away?
Confusion is often a big part of warfare, especially back in ww1, were there cases of people suddenly ending up where they shouldnt be?
The concept of a triple border with one nation being neutral is just... weird to me.
Thanks for any answers
I think I can answer a few of your questions
Yes, borders were well defined, this was after all Europe in the 20th Century.
What's to stop soldiers doing it anyway? I think there's something to unpack here. At the start of the war, the French plan was to push forward on the common border with Germany (the Battle of the frontiers) which was fairly disastrous from the French point of view, incurring several hundred thousand casualties with little to show for it.
However, one of the territorial gains was the small town of Pfetterhouse/Pfetterhausen, so the actual terminus of the front was in German territory rather than the existing Swiss/French/German triple-point.
Now both France and Germany did have plans to invade through neutral Switzerland. The French plan was called Plan H unfortunately I don't know much about the German plan.
But invading a neutral country is not a cost free enterprise. Apart from gaining yourself a shiny new enemy, you also earn yourself international condemnation with the risk that other countries might flip from neutral to enemy or at least 'armed neutrality' - As the Germans found out when they invaded through Belgium.
If we're talking here about an unofficial and unsanctioned, or even unintentional incursion by either side, well, the Swiss had constructed quite serious fortifications to guard against that including their own trenches, watch towers, and electric fences with enough current to kill you to death (RIP). So not much chance of a little 'whoopsie'
So yes, the neutral nations guarded their own neutrality but there wasn't that much fighting going on. Short of violating Swiss neutrality, operations at the terminus of the front were necessarily going to be constricted so it wasn't the ideal place to launch a major offensive - further complicated by all the hills and forests and other impediments.
French trenches in red, German trenches in blue.
So TL;DR the trench line did sort of just stop but everyone was pointing guns at each other.