For those wishing to visit Greece and, by extension, the Schengen Area, a visa may be required depending on the country of origin. The list of countries requiring or not a visa can be found at the web site of the Hellenic Republic Ministry of Foreign Affairs (https://www.mfa.gr/en/visas/).
The Conference Secretariat of TRNA2026 will be happy to issue a letter of invitation to participants wishing to apply for a visa.