Boyloso/Shutterstock Icelandair is rebuilding its US route network as Iceland opens to vaccinated tourists. Regular flights to Boston, New York, Seattle, Chicago, Denver, and Washington, D.C. are scheduled for May. Americans need only their paper vaccination card to enter the country. The summer of vaccinated travel now includes Iceland as a potential destination for Americans. Starting April 6, vaccinated travelers from the US will be allowed into Iceland with just their paper vaccination certificate from the Centers for Disease Control and Prevention. It's the first European country to open its doors to Americans with no testing or quarantine required for visitors upon arrival, creating a potential boom for tourism and the country's national airline.