Enlarging the hallway floor plan REH from 1921: Tips?

Well, it supports the wall above. If we removed it at the bottom, there could be cracks in the wall above or it could collapse. The whole house would not collapse.

When you read about party walls, all of that is correct. I wouldn't have thought so either, but it is.

and how wide should the kitchen be? I ask because you write something about a U. Why do you think the U is a good solution for the room?

Because we have the space :). The kitchen planning is done by a full-time kitchen planner, whose kitchens I know quite a few of. He knows what he’s doing.

Here's an update on the project:

The ground floor has been gutted. We torn down the part of the wall that was at the top side next to the kitchen door. We left the rest of the wall standing. It was/ is not load-bearing, as later turned out.
The kitchen plans have changed a bit again, which is why we didn’t want to set back the entire wall. Instead, we gained about 14 cm of passage width at the old vestibule by removing the beam of the old door frame and a piece of the wall there. Since the stove has now been moved to another spot, closer to the dining area, it would have become too tight if we had further recessed the wall opposite that point.
The Ikea kitchen will be ordered the day after tomorrow:

Currently, the new interior plaster is being prepared. The new niche will be realized with drywall construction. So at the moment, we have a semi-open kitchen space and could take another look at the open concept this way — and for sure, it’s not for us.

Dusty greetings from the big construction site!