it all depends krieg. Some were buried so it's hard to say. At the Cezembre island near St malo, Germans got shelled for days and some survived.

Here is another great bunker. I found this by chance. I climbed on a panorama artificial hill made next to a giant dike at the Rhine delta. This is how I spotted this bunker on on farmland. It was impossible to get closer as it was behind tracks and fenced . The farmer uses it as a stable and a shed. It looks pretty intact !

click on the picture to enlarge it.

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