Designed in the International style by Richard Roth, Walter Gropius, and Pietro Belluschi and completed in 1962, the MetLife Building is 808 feet (246 m) tall with 59 stories.

[22] Though Walter Gropius had considered a precast concrete facade to be more solid than a glass curtain wall, this only made the building appear bulkier.

[14] Furthermore, the appearance of concrete degraded over time; this effect could be seen in structures such as the Solomon R. Guggenheim Museum but was more pronounced on the MetLife Building's facade.

[45] 200 Park Avenue was built atop two levels of railroad tracks underground, which feed directly into Grand Central Terminal.

[23] A "triple decker sandwich" made of lead, asbestos, and sheet steel was installed under each level of tracks to provide insulation.

[56] The heliport's opening required approval from the Federal Aviation Administration (FAA), the city government, and the Port Authority of New York and New Jersey.

[66] The service was operated by New York Airways, which flew Vertol 107 helicopters from the rooftop helipad to Pan Am's terminal at John F. Kennedy International Airport (JFK).

[67][79] The already-controversial building received further negative attention as a result of the incident, and both New York Airways and Pan Am suffered financially in subsequent years.

[79] During its short periods of operation, the heliport was largely perceived as a nuisance and danger, but its presence was also seen as satisfying what David W. Dunlap described as "the consummate technological fantasy of airborne travel through skyscraping pinnacles".

[92] In an early-2000s renovation by Kohn Pedersen Fox, the lobby received tile and black travertine floors, the storefronts were moved to the side, and the central staircase was removed.

[105] The composer John Cage, a friend of Lippold's, had initially proposed a musical program to complement Flight,[102][106] consisting of ten loudspeakers, which would have played works by Muzak whenever people walked in and out of the lobby.

[35][107] At the Pan Am Building's opening, the entrance from the Main Concourse was topped by Manhattan, a 28-by-55-foot (8.5 by 16.8 m) mosaic mural of red, white, and black panels by Josef Albers.

Pan Am, the airline for which the building was originally named, contained a ticketing office at 45th Street and Vanderbilt Avenue, similar in design to Eero Saarinen's TWA Flight Center at JFK Airport.

[80] By the 1950s, passenger volumes at Grand Central Terminal had declined dramatically from the early 20th century, and there were proposals to demolish and replace the station.

[129] In February 1955, Wolfson, the Scheftels, and Alfred G. Burger proposed a 65-story tower called Grand Central City, which would replace a six-story baggage structure north of the terminal.

[146] In January 1958, representatives of an unnamed large company, who were unaware of Grand Central City's cancellation, notified Stuart Scheftel that they were interested in leasing space in the new building.

[161] A week after being hired, Gropius suggested that the slab be oriented east–west, with a large plaza or courtyard in front of the tower, similar to the design of Lever House.

[26][164][165] The Roth firm said the octagonal massing could absorb "different planes of light as on a diamond", while Gropius said the new alignment was easier for air conditioning.

[178][179] Construction on the structure officially started two days afterward on November 26,[180] and Cushman & Wakefield were named as leasing agents for Grand Central City the following month.

[182] Gropius was involved in all aspects of the building's design, from traffic flow to minor architectural details, which sometimes led to conflicts with the project's other architects and engineers.

For example, he wanted the lobby's bronze details to contain a matte finish, and he requested that the elevator penthouse be no higher than 26 feet (7.9 m) above the roof so that it did not "look silly".

[95] The as-yet-incomplete Pan Am Building was formally opened on March 7, 1963, with a ceremony attended by British and American officials,[175][199] and tenants started moving into the structure the following month.

[204] This contrasted greatly with the smaller Empire State Building, which was only 25 percent rented when it opened and did not reach full occupancy for more than a decade afterward.

[218] That year, Pan Am bought a 45 percent stake in the building from the estate of Jack Cotton,[206] formerly chairman and co-owner of City Centre Properties.

[247][252] At the time, Donald Bren, the billionaire owner of the real estate firm Irvine Company, held a 97.3 percent ownership stake in the building.

[27][268] Grand Central City was lambasted internationally by Italian critic Gillo Dorfles and Romanian architect Martin Pinchis.

[269] Architect Victor Gruen questioned the parking garage's necessity given the site's proximity to a major railroad terminal,[270] while Progressive Architecture editor Thomas H. Creighton suggested the space would be better left as an open plaza.

[14][29] Gropius said the 1916 Zoning Resolution justified the building's large size, telling television presenter Dave Garroway that "every citizen has the right to use the law as far as he can";[274][275] this only prompted further negative reviews.

[274] James T. Burns Jr. wrote in Progressive Architecture that the placement of the base, tower, parking garage, and Grand Central Terminal were "occasionally inexcusably jarring" and considered the lobby to be a continuation of the exterior's "monolithism".

[34][285] Paul Goldberger of The New York Times said that even though the previous design was "stark and unwelcoming", the new decorations created "a space that is so forced in its joy, so false and so disingenuous, that they make one yearn for some good old-fashioned coldness".