American citizens traveling for tourism are not required to have a visa for this initial entry into the Schengen area, but must have a passport valid three months beyond the proposed stay (for a two month holiday the passport must be valid for five months, for example.)
Although European Union regulations require that non-EU visitors obtain a stamp in their passports upon initial entry to a Schengen country, many borders are not staffed with officers carrying out this function. If an American citizen wishes to ensure that his or her entry is properly documented, it may be necessary to request a stamp at an official point of entry. Under local law, travelers without a stamp in their passports may be questioned and asked to document the length of their stay in Schengen countries at the time of departure or at any other point during their visit, and could face possible fines or other repercussions if unable to do so.
Please note that non-U.S. passport holders are responsible for obtaining the required documentation applicable for their entry.