Update 2021-03-16: As of Thursday (18 March), all persons who have been vaccinated against COVID-19 are allowed to enter Iceland again. Previously, this regulation only applied to travellers from the Schengen area. Persons who have been vaccinated do not have to undergo any further tests or quarantine. As proof of vaccination, either a “Yellow Card” from the WHO or a vaccination certificate from a Schengen state must be carried.