Zohran Mamdani is set to be sworn in as New York City's next mayor in a private ceremony shortly after midnight on New Year's Day. The unconventional event will take place in the abandoned Old City Hall subway station beneath City Hall Park, with Attorney General Letitia James administering the oath. Mamdani stated the location symbolizes a new era and the city's legacy, while James noted it represents Mamdani's fight for a city where all New Yorkers can thrive.