New Delhi, Jan. 1 -- Zohran Mamdani officially took office as mayor after the New Year's Eve ball drop, in a private ceremony held at a shuttered relic of the city's subway. A millennial, South Asian and Muslim leader, Mamdani became the city's first Muslim mayor-and the first to swear his oath of office on the Quran.

The inauguration will unfold in two distinct ceremonies, blending symbolism, faith and the city's layered history. A private midnight swearing-in will take place in a disused subway station beneath City Hall, followed later in the day by a public ceremony on the steps of City Hall.

During both ceremonies, Zohran Mamdani will place his hand on the Quran, Islam's holiest text, making him the first mayor in New York City to d...