According to the Robert-Koch-Institute, Denmark and the Netherlands are no longer risk areas! This means that tourists from Denmark or the Netherlands currently no longer have to register on the portal at www.einreiseanmeldung.de
For all tourists, however, a negative rapid test must still be shown at check-in in Lower Saxony.
Children up to and including 14 years are exempt from this rule, as well as those who have been fully vaccinated (for at least 14 days) and those who have recovered (for at least 28 days and max 6 months). A vaccination card or a convalescent card must be shown on arrival!