This article is from the Europe FAQ, by Yves Bellefeuille firstname.lastname@example.org with help from Martin Rich M.G.Rich@city.ac.uk.
Violent crime is much less a problem in Europe than in the USA. You
shouldn't be overly worried about being robbed or mugged. However,
pickpockets seem to be more common in Europe than in some other
countries. In general, no special precautions are necessary when
travelling in Europe; just use normal prudence.
European cities usually don't have "dangerous" neighbourhoods or areas
in the way that some US cities do.
Weapons are regulated much more strictly in Europe than in the USA,
especially firearms. Don't carry any weapons, including mace, pepper
spray, and so on, unless you've checked with the police or consulate of
the country concerned to ensure that they are legal.