I'd think German traffic engineers could come up with a better solution, yet these are everywhere:
The bike paths themselves are desire paths for cars and motorcycles.
To block them off, they put up barriers, but those also block cargo bikes, wheelchairs and strollers, create a collision hazard, and force all cyclists to stop and dismount for no reason.
Of course, they'll be bypassed wherever possible – naturally by cars and motorcycles too, if there's enough room.
Those look annoying. Here they use bollards with a collapsible one on the centre so you can easily walk/bike through the gaps but maintenance vehicles can still get through with a key. Guess they don't prevent motorcycles but neither do the gate style in the OP.
I don't understand why they don't just use 2 posts 1.8m apart on either side of the bike path.
It would be much safer and more convenient for cyclists and still keep cars out.
Motorcycles usually aren't an issue on these paths, except for the occasional old guy or youth on a 50cc, and there's nothing that keeps them out and lets cyclists through.
The bigger bikes want to go faster than is possible on those paths.
noise activated land mines!
Huh. I wonder... could you create an EMP mine powerful enough to fry the electrical system of a car or motorcycle? Interesting idea.
At least for the dams I can answer that. The posts, if removed, are a hazard when there is a flood. You’d need extra man power/time to collect excess posts in a moment when these factors are critical in fighting against flooding. Yes, it’s not the standard to drive atop the dam, but before starting to fortify it there needs to be a measurement of how well it’s doing where.