U.S citizens can stay in Spain for 90 days at a time for travel without a visa. Anything over this requires a visa or you will be deported.
Starting with the 2011 New Year, you may not stay in Spain for more than six months if you do not provide a criminal background check by the FBI to Spanish consular officials in the U.S. when applying for a visa. You will also need to get a letter from the U.S. Embassy requesting that your local police take fingerprints to go with the records.
Liquids, such as shampoos and other hygiene products, that are in carry-on bags, must be in a clear plastic quart-sized bag so that inspectors can see them clearly.
