Hi TRIPLE-SSS
I come from Poland, living in Germany.
Officially it is illegal to detect in Poland, everything in the ground belongs to the state, and everything older than 50 years or so has to be reported.
So much for theory.
In practice you can detect as much as you want, the police only care if you dig on an archaeological site ( a no-no) or digging up explosives.
most times they do not bother you , sometimes want to see what you found to make sure it's not grenades etc. I guess most problems are with farmers not allowing you to detect, as everywhere in the world i guess. All in all Poland is a great place to detect, many forgotten places, a lot of turbulent history, loads of free land to detect (unlike in Germany where all land is divided and fenced and cultivated, in Poland you find a lot of meadows and general wilderness). A lot of competition though
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In general the more east you go in Europe, the more freedom you enjoy
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As far as i know only in England detecting is allowed without any permits, everywhere else a permit of some kind is required, in some countries it is hard to get them, and in some countries it is forbidden altogether, just beaches are ok (sweden ? italy ? greece ?). All in all for a visitor it usually makes no sense, since it is a long process to get a permit, you need to visit various institutions, submit applications etc.
But again, in most places it is not considered a real felony when you just go out in a field and detect, it is good practice to have a permission of the land owner of course. Stay clear of all archaeological sites and you should be ok. In France, if they catch you detecting without a permit, they can, and most probably will, take away your detector. So beware. In Germany you also need a permit, depending on the land you are in the laws differ, some lands the forests are off-limits, some not. Again, i have been detecting here for 5 years or so, no permit, never had any problems really. Naturally, i try to stay out of sight, no point increasing the chances of running into authorities. Just use common sense, ask for permissions of the landowner if you can locate them, be friendly to people inquiring into what u r doing.
If you find something extraordinary, then you have a problem though
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You should report it, but then you have no permit...
But that is another story, and till now i haven't had to think about this since i never found a treasure of any kind.
Good luck and post your finds when u r back !
Cheers !