Short answers, pulled from the story.
Riverside Church is located in the Morningside Heights neighborhood of Manhattan, occupying the block bounded by Riverside Drive, Claremont Avenue, 120th Street, and 122nd Street. It sits near Columbia University's Morningside Heights campus and across from Grant's Tomb.
Riverside Church was conceived by philanthropist John D. Rockefeller Jr. in partnership with Baptist minister Harry Emerson Fosdick. The original church building opened on the 5th of October, 1930, with a service attended by 3,200 people.
Riverside Church's 74-bell carillon is the largest in the world by aggregate weight; the bells and associated mechanisms weigh a combined 500,000 pounds. The bourdon, the lowest bell, weighs 20 tons and is the world's largest tuned bell. The bells can reportedly be heard from up to 8 miles away.
The tower of Riverside Church rises 392 feet, making it the tallest church in the United States and among the tallest in the world. The tower contains 21 usable floors, including 80 classrooms and office rooms.
On the 4th of April, 1967, Martin Luther King Jr. delivered Beyond Vietnam: A Time to Break Silence at Riverside Church, in which he voiced his opposition to the Vietnam War. The speech was given a year before his assassination.
Riverside Church was built in the Neo-Gothic style, designed by Henry C. Pelton and Allen and Collens and modeled primarily on the thirteenth-century Chartres Cathedral in France. Despite the Gothic exterior, the building's internal structure uses a modern steel frame and curtain walls.