Denmark
Airsoft guns are mentioned in the Danish "Våbenlov" (arms control legislation). You have to be at least 18 years old to buy, hand over or possess airsoft guns. They may be used on police-approved sites, with a permission slip, at the age of 16. A firearms certificate is not required. All airsoft guns have to be transported concealed in a bag or in the trunk etc.
Read more about this topic: Legal Issues In Airsoft