270 Park Avenue, also known as the JPMorgan Chase Tower and the Union Carbide Building, was a skyscraper in the Midtown Manhattan neighborhood of New York City.

Built in 1960 for chemical company Union Carbide, it was designed by the architects Gordon Bunshaft and Natalie de Blois of Skidmore, Owings & Merrill (SOM).

About two-thirds of 270 Park Avenue was built atop two levels of underground railroad tracks, which feed directly into Grand Central Terminal to the south.

[6] On the site of 270 Park Avenue, the developer Charles V. Paterno constructed the six-building Hotel Marguery complex,[1][7] which opened in 1917.

[9] At the time, the section of Park Avenue north of Grand Central Terminal contained many apartment houses for the rich.

The sidewalk in 270 Park Avenue's plaza was so slippery that, less than a year after the building was completed in 1960, acid etching was applied to the tiles to roughen their surfaces.

[45] At the center of the site, separating the main 52-story tower and the Madison Avenue annex, a 60 ft-wide (18 m) wide public plaza connected 47th and 48th Streets.

[51] About two-thirds of 270 Park Avenue was built atop two levels of underground railroad tracks, which feed directly into Grand Central Terminal to the south.

Ninety-five steel stilts, which had supported 70 percent of the former Hotel Marguery, were replaced by heavier columns that could carry the newer building's weight.

[30][33][57] Escalators from the ground story led to the second-story mezzanine,[57][56] flanking an elevator core with red wall cladding.

[4] When Manufacturers Hanover took over, the eighth and ninth floors were remodeled into an executive suite with both modern and antique art, as well as an internal connecting staircase.

[69][78][81] Though the ziggurat plan would have been 200,000 sq ft (19,000 m2) larger than the 48-story tower, Union Carbide rejected the proposal because the interior offices would have been too dark.

[87] A refrigerant compressor for an air-conditioning chiller, weighing 43,000 lb (20,000 kg), was installed on the roof in July 1959; at the time, no other similarly heavy object had been hoisted to a higher altitude.

[109] After Penn Central went bankrupt that year, the company sought to sell its properties, including the land below the Union Carbide Building.

Union Carbide submitted a bid for its own building, and Corporate Properties also offered to buy the structure and nine others for $87.9 million.

Union Carbide started negotiating to sell the building to a bank, Manufacturers Hanover Trust, which itself had been looking to expand from its headquarters at 350 Park Avenue.

[116] Union Carbide acquired the land from Penn Central in 1976 for $11 million and signed a letter of intent with Manufacturers Hanover the next January.

[117] Although Union Carbide was planning to move away, the transaction made it easier to sell the building, as the structure itself and its land were now under common ownership.

[117][119] The space appealed to Manufacturers Hanover because of its proximity to Grand Central Terminal and because buying and renovating the existing structure was cheaper than erecting a new building.

[59] SOM designed the changes, which included removing the mezzanine level; renovating the plaza, where it added two fountains; and refurbishing of interior flooring, ceilings, and fixtures.

[15][154][156] The American Institute of Architects' New York affiliate expressed concern that the demolition and reconstruction of 270 Park Avenue would be energy-intensive,[15] especially as the building had achieved LEED status less than a decade earlier.

This raised concerns that the new building would require deeper foundations that could interfere with the MTA's East Side Access tunnels and Grand Central Terminal's rail yards.

[165] In July 2019, the MTA and JPMorgan Chase signed an agreement in which the bank agreed to ensure that the destruction of 270 Park Avenue would not disrupt the timeline of East Side Access.

[149] When the building was completed, Architectural Record said that "the detailing is a further step in the direction of simplification and clarity of statement" compared to previous designs by SOM.

[71] Anthony Paletta of The Wall Street Journal said in 2013 that "the Union Carbide Building is a bracing exemplar of postwar corporate modernism".

[177] The author Eric Nash wrote that "the Union Carbide is flawed architecturally", with an uninviting plaza and a "derivative" facade.

[13] When the building's demolition was announced, Justin Davidson of New York magazine characterized the structure as "appearing gracious and vibrant, the incarnation of white-collar America".

"[57] The architect Annabelle Selldorf said in 2020: "The Landmarks Preservation Commission can only protect so many buildings, which means some children are left behind, and Union Carbide is one of them.

"[178] The journalist Roberta Gratz wrote: "The planned destruction of 270 Park exemplifies how a vital aspect of the urbanism on which this city has evolved and excelled over decades is now being dangerously eroded.

"[155] Similarly, Reese Lewis of the Brooklyn Rail said in 2024 that, despite the Union Carbide Building's significance, it had been demolished "at a moment when it is so inappropriate to do so".