Following explicit confirmation from the Police Border Guard Headquarters in Poland, U.S. citizens are no longer entitled to remain visa-free in...
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From what I read, the rule has been the same since 2006, but the new system uses biometrics, which will make enforcement easier. It probably forces countries to not allow overstays by sharing the data with the eu authorities.
90 out of 180 days at least makes some sense. I don't know what the rules are in the US now, but pre 9/11 it used to be that if a person was visiting here, they had 90 days. But to re-set the 90 day period, all you had to do was leave the country and get your passport stamped. You could come back the same day if you wanted.