Rockefeller Center is a complex of 19 commercial buildings covering 22 acres between 48th and 51st streets in New York City, United States. Built by the Rockefeller family, it is located in the center of Midtown Manhattan, spanning the area between Fifth Avenue and Sixth Avenue. It was declared a National Historic Landmark in 1987.Rockefeller Center was named after John D. Rockefeller, Jr., who leased the space from Columbia University in 1928 and developed it from 1930. Rockefeller initially planned a syndicate to build an opera house for the Metropolitan Opera on the site, but changed his mind after the stock market crash of 1929 and the Metropolitan's continual delays to hold out for a more favorable lease, causing Rockefeller to move forward without them. Rockefeller stated "It was clear that there were only two courses open to me. One was to abandon the entire development. The other to go forward with it in the definite knowledge that I myself would have to build it and finance it alone."He took on the enormous project as the sole financier, on a 27-year lease for the site from Columbia; negotiating a line of credit with the Metropolitan Life Insurance Company and covering ongoing expenses through the sale of oil company stock. The initial cost of acquiring the space, razing some of the existing buildings and constructing new buildings was estimated at $250,000,000.It was the largest private building project ever undertaken in modern times.Construction of the 14 buildings in the Art Deco style began on May 17, 1930, and was completed in 1939. Principal builder and "managing agent" for the massive project was John R. Todd. Principal architect was Raymond Hood, working with and leading three architectural firms on a team that included a young Wallace Harrison, later to become the family's principal architect and adviser to Nelson Rockefeller. The construction of the project employed over 40,000 people.It was the public relations pioneer Ivy Lee, the prominent adviser to the family, who first suggested the name "Rockefeller Center" for the complex, in 1931. Rockefeller, Jr., initially did not want the Rockefeller family name associated with the commercial project, but was persuaded on the grounds that the name would attract far more tenants.What could have become a major controversy in the mid-1930s concerned the last of the four European buildings that remained unnamed. Attempts were made by Ivy Lee and others to rent out the space to German commercial concerns and name it the Deutsches Haus. Rockefeller ruled this out after being advised of Hitler's Nazi march toward World War II, and thus the empty office site became the International Building North.This subsequently became the primary location of the U.S. operations of British Intelligence, British Security Coordination during the War, with Room 3603 becoming the principal operations center for Allied intelligence, organized by William Stephenson, as well as the office of the future head of what was later to become the Central Intelligence Agency, Allen Welsh Dulles.