Hello, yesterday we drove across the Stiftungsland and it is really beautiful. However, this section also meant that we had to cancel our tour. The foundation land had probably been mowed a few weeks ago and that meant that everything was full of thorn branches. We had a total of 12 holes, then the patches weren't enough. Two e-bikers felt the same way. Everything flat. I would not recommend driving there. Tubeless might work, but I would have concerns about that too. If you want to see pictures, here is the link to our tour including thorns ;) komoot.de/tour/701818358
We were there today, July 2025, with our gravel bikes. In recent winters, several meters of the cliff edge have collapsed during storms. And now it's very confusing to find the right path. The thicket is really extremely difficult to navigate. And make sure you stay on the right side of the fence; the old path eventually becomes a dead end, and then you'll have to go all the way back. So be careful.