Are U.S. citizens permitted to enter? Yes.
Is a negative COVID-19 test (PCR and/or serology) required for entry? No.
Regulations continue to change so before traveling to Romania, please consult your airline as well as the Embassy of Romania in Washington, D.C. (here) or in the country of your departure for entry requirements
Lot of foreigners here, many of them Europeans with travel experience in Europe? Lot of people here willing to share helpful information. Forumosa isn’t a bad place to ask. I’d probably check the Finish health department or immigration agency too, but PornHub? Unless… you are seeking advice about PCR test requirements for entering Finnish saunas…
Centre has closed, I guess very few travellers need exams, only some nations require it from certain areas.
Do hope Asian flights come back, Air Japan and Finn Air have some flights but not yet back to normal levels. COVID was a problem and now other problems