After 54 years of animosity, the United States and Cuba have formally restored diplomatic ties.
That means that the U.S. opened an embassy in Havana and Cuba opened an embassy in Washington, D.C., this morning.
In truth, both countries had for years already been running robust interest sections in both capitals. Today, however, both of those missions were upgraded.
And this afternoon, the Cuban flag will be raised on the grounds of the Cuban embassy in Washington for the first time since 1961.
Secretary John Kerry will travel to Havana to do the same at a later date.
Conrad Tribble, the deputy charge d'affaires at the U.S. Embassy in Havana, tweeted shortly after midnight that he had phoned the State Department.
"Just made first phone call to State Dept. Ops Center from United States Embassy Havana ever," he tweeted. "It didn't exist in Jan 1961."
If you remember, this process kicked off in December, when President Obama and Cuban President Raúl Castro announced their intention to normalize relations. Since then, the U.S. has eased some travel and economic restrictions and removed Cuba from a list of state sponsors of terrorism.
NPR's Carrie Kahn is in Havana for the occasion. She filed a piece for Morning Edition that takes a look at the history of the old U.S. Embassy in Havana:
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