Why did the Maginot line was built along the lines where it was at 1930s.

by RyoTGZ

As far as I understand that it was more of a defence race between Germany and French as both sides rapidly armed and fortified their side of the Maginot line.

But why not go further south to borders Switzerland? Why a German flank wasn't expected from there as ocupation/invasion of Switzerland was a possible option for German Blitzkreig?

About the Belgium fortifications; my understanding is that French expected the fortifications and defensive measurements to be strong enough to hold Germans back or at least slow them down.

Why did French relied on Belgian defences in such confidency?

DanKensington

I dug around to see if your question popped up before, which it has, and I commend to your attention these following excellent answers:

  • On the matter of Switzerland, u/unveiledignorance explains the difficulties of opening up a front via a country in the middle of the Alps.
  • Also on Switzerland, u/Georgy_K_Zhukov has this extensive examination on Switzerland during the war, especially on what their stance of 'armed neutrality' entailed.
  • On the far side of the line, u/kieslowskifan expands on the Franco-Belgian thinking behind how the defensive arrangements were intended to work in Belgium.