mattf, while I agree that an age restriction of 21 for buying alcohol is a little weird (even if it's rarely enforced), I don't think we have much to boast about in the UK. We have huge drink problems with young people here. Two of my friends started drinking heavily during the week in their late teens and had become alcoholics by their early twenties. But it's a cultural problem, not a problem with drinking laws.
Regarding the age of consent to sexual intercourse, I think in Spain it's 13 (it used to be 12). That seems too low to me. I know 13-year-olds who definitely aren't mature enough to make an informed decision about the risks involved (though I suppose I also know 25-year-olds who seem equally immature...
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