https://www.necn.com/news/local/maine/maine-ends-covid-19-travel-requirements/2458437/

In the state of Maine, all Covid-19 travel restrictions have been lifted. Visitors will not be required to have a negative Covid-19 test or quarantine after arriving. This policy is due to the evidence from their previous tourist season where there was only a small amount of virus transmission. If there happens to be a spike in positive cases, the state will look to reenacting restrictions.