Since 2007 the Czech Republic has been a member of both the European Union and the Schengen area.
Citizens of countries that are also in the European Union and the Schengen area may stay in the Czech Republic with no permit requirements. They only need a valid travel document or an ID card. If anyone stays in the Czech Republic longer than three months, he or she must notify the relevant authorities of their stay.
With or without a visa
The list of countries whose citizens may travel for a short term to the Czech Republic with only a valid travel document, without a visa, can be found here.
The list of countries whose citizens must have a relevant valid visa to enter the Czech Republic can be found here.
The official Tourist Website for Prague: http://www.prague.eu/
Notes: You must be registered for the event before requesting a conference invitation letter. Provision of the invitation letter by SSIP2019 does not guarantee visa approval, which is made at the sole discretion of the government of the event’s host country.