The post of our driveway gate protrudes about 10 cm onto the neighboring property

Did the new neighbors actually send their architect ahead? Have the gentleman give you the names and addresses of his clients, call them and say: we need to talk! This is initially about the way of communication. This will put you in a better position.

According to the internet, a neighbor's right expires after 3 years regarding dismantling or similar. What do you think about this?

Hello

I just read through the thread.
The bad neighbor simply claims that the dear homeowner is 10 cm on the neighbor's property. And the internet says that if he doesn't notice it for 3 years, he's out of luck.
My property is my property. And if I notice that my neighbor is using my property, then I expect a proposal from the user to resolve the matter.
This can be dismantling or monetary compensation. But no sticking out the tongue: "ha, you didn't notice for 3 years," is not constructive.

Steven

Unfortunately, did not keep us updated on how the matter progressed. Interesting that it is being discussed again now.

the tone is quite harsh, but on the other hand it is correct to point out that every issue has two sides. The OP certainly presented his view. Whether he was right, we never found out. But the demolition of the fence does cast a bad light on the "other side".

But the demolition of the fence does cast a bad light on the "other side."

Hello Altai

correct.
But we never found out where the fence stood. And in what condition the fence was.
Assuming I buy a property, there is an old wooden fence on it. Now I develop the property into an urban area. A few old boards quickly end up in the dumpster.

Steven

Suppose I buy a piece of land, on it is an old wooden fence. Now I urbanize the land. A few old boards quickly go into the container.

Before the demolition begins, I visit the other party and introduce myself. And there you can agree on boundaries.

Don't know what was written here, but the right way would have been to have a publicly appointed surveyor determine the boundary. Then one could have looked further.