FCDO advice including information on permitted duration of stay and visas for Denmark: www.gov.uk/foreign-travel-advice/denmark
There are various sources for information on the latest restrictions in force due to the Coronavirus pandemic:
RYA Covid-19 hub - https://www.rya.org.uk/coronavirus including advice and information for recreational boaters at https://www.rya.org.uk/coronavirus/advice-for-boaters.
Information on entry requirements can be found at https://www.gov.uk/uk-border-control?priority-taxon=774cee22-d896-44c1-a611-e3109cce8eae
Noonsite - https://www.noonsite.com/place/denmark/
Re-open EU – https://reopen.europa.eu/en
For information on the validity of RYA certificates abroad see Evidence of Competence Abroad.
Evidence of competence is required for some powerboats under the Danish flag. The RYA has been advised that this requirement does not extend to foreign flagged boats.
For foreign flagged vessels, there is no specific requirement for evidence of competence other than that stipulated by the vessel's flag state.
EU member state (part of the customs territory of the EU (which includes territorial waters)). Further information is provided on the Entry & Exit Formalities page under Customs - EU Member States.
Part of the Schengen area.
As part of the customs territory of the EU (which includes territorial waters) and the Schengen area customs and immigration checks may not always be required on arrival and departure.
See holding tanks for information on the discharge of waste water.