Depending on your nationality and the intended length of your stay, you might need a visa for entering the Czech Republic.
Nationals of the EU, Switzerland, Iceland, Liechtenstein and Norway do not need a visa for their stay in the Czech Republic, irrespective of the length of their stay.
With the Czech Republic's accession to the EU on May 1st 2004, EU nationals are allowed to enter the country using only their passport.
Visitors of the Czech Republic from the following countries do not need a visa for a stay up to 90 days either, due to bilateral agreements:
Albania, Andorra, Antigua and Barbuda, Argentina, Australia, Bahamas, Barbados, Bosnia and Herzegovina, Brazil, Brunei, Canada, Chile, Costa Rica, Croatia, Guatemala, Honduras, Hong Kong, Israel, Japan, Macedonia, Macao, Malaysia, Mauritius, Mexico, Monaco, Montenegro, New Zealand, Nicaragua, Panama, Paraguay, St. Christopher and Nevis, El Salvador, San Marino, Serbia, Seychelles, Singapore, South Korea, Taiwan, Trinidad and Tobago, USA, Uruguay, Vatican and Venezuela.
Anyone arriving with a Schengen visa, whether directly into the Czech Republic or via another Schengen country, will not need another visa, as long as it is not issued by another EU country with a status of limited territorial validity.
Non-EU citizens, with a family member who is an EU citizen, who hold a temporary or permanent residence permit in another EU country, do not need a visa to enter the Czech Republic.
All other nationals need to acquire a visa before coming to the Czech Republic. Although Transit Visas are usually given out on the same day, the general application process may be very time-consuming.
Note: All foreigners visiting the Czech Republic need to provide proof of their health insurance!