Diggers Grandson - The laws pertaining to war relics are dependent on the country you're in and can vary from 'You can do what you like when you like', to 'Touch anything and we'll throw you in jail'. It is difficult to know what law applies where as you travel europe, but one of my French colleagues helped out about a year ago, following an encounter with a Forestry guy. I shall quote directly from his post so please excuse the language used.......his English is good, but not brilliant
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.....On our first search day (we had the intention to dig very carefully), we are deep in the forest when we got caught by a Forestier. A Forestier, is a French forester. Some Forestier has something more judicial powers then the foresters we are used to. Adorned with gun and handcuffs he told us the following:
1. The battlefields of France have been declared to historical sites of the French state;
2. All items in or on the battle fields is owned by the state;
3. Taking something / or picking up is the theft of the French state;
How futile, rusty or trivial picked up the article may be the law condemns it as theft of the French state for which the fines are strict.
However, if they have the impression it has to do with tourists with a purpose other than a 'souvenir' pick is also another law (eg in the Somme, Champagne, Verdun, Meuse and Argonne)
Have in possession:
1. A detector
2. Spades or any digging tools of any kind
3. Parts of or whole ammunition or shell or fuse
Then immediate confiscation of their vehicle until the fine (FF 20,000 / € 3100, -) is payed. The French government is willing to containment of the offender (s) until this decision is respected.
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So I am afraid you fell foul of French law and were lucky to get away with a seizure notice.
I still see people posting about how it is ok to dig in France and recover relics. Trust me, it isn't, and the guys that say these things are either DAMN lucky or just dig at night with an IR torch.
Hope that helps
ww2digger