Travel.State.Gov > International Travel > Before You Go > Travelers with Special Considerations > Traveling In Europe
If you are planning to visit or travel through European countries, you should be familiar with the requirements of the Schengen Agreement. The Schengen Agreement is a treaty creating Europe's Schengen Area, which encompasses 26 European countries, where internal border checks have largely been abolished for short-term tourism, a business trip, or transit to a non-Schengen destination.
For information on the March 11, 2020 Presidential Proclamation on travel from and transiting through Europe, see our Frequently Asked Questions here.
Schengen area countries may reinstate temporary internal and external border control without advanced notice. U.S. citizens should carry their U.S. passport at all times when traveling to/from and within the Schengen area.