A Greece Passenger Locator Form is required if you are traveling to Greece and must comply with local route and trace requirements prior to boarding the plane. The form could be filled out in person or by mail, fax or email. In any case you'll be asked to provide evidence of your identity, a current photograph and a copy of your passport. You'll also be required to announce in which you live and any other location which you would love to go to Greece. A PLF is a legal document that proves that you have lawfully traveled to Greece and received the necessary travel documents.