For much of 2021, US passport holders have seen an expanding list of international travel options. But with the rise of the Delta variant of Covid-19, that list has started contracting a little.

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List of nations

What follows is a curated, alphabetical list of countries and territories where it's still possible for US passport holders to go for a vacation. Click the links at the end of each destination for important information on:

-- Presenting negative results from Covid-19 tests to enter (including time limits to take the test, types of tests allowed and additional tests upon arrival).

-- Quarantines (if any) and health screenings.

-- Possible exemptions from the rules for the fully vaccinated, people recovered from a recent case of Covid-19 or children.

-- Health insurance requirements, curfews and lockdowns.

-- Different rules if you're arriving from a third country vs. the United States.

These are all things you need to research before you book your trip. People testing positive for Covid-19 upon arrival or while visiting can expect to go into quarantine. Rules for land entry may be different.

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