Berenice Abbott shot the portrait above of the old City Hall Post Office (with Woolworth in the background) in 1938, a year before the building was demolished, to be replaced by an extension of City Hall Park and some road improvements. One of the amusements provided by the use of revivals of historic architectural styles is that the modern building in her photo is the Gothic skyscraper, not the Second-Empire post office.
The post office was not well-loved for its design and probably was doomed by its site. The federal government had wanted a site in New York’s business district for the building (the city’s general post office, service as the interaction point between local and national mail) but putting it at the southern tip of the park’s triangular shape meant that the building was hemmed in by two busy streets (Broadway to the west and Park Row to the southeast). The loading docks faced north onto Mail Street, a very short street connecting the two main streets and giving the park a somewhat industrial southern view.
The building was gradually overwhelmed by the quantity of national mail – New York’s population was 1,160,000 in 1880, when the building’s 11-year construction period ended and 6,930,000 in 1930 – and was isolated from the railroads that carried long-distance mail. Its replacement, the General Post Office on Eighth Avenue, was directly over the platforms of Penn Station, and opened in two phases, 1914 and 1935. That building took over the role of being the city’s postal hub in 1918, which marked the beginning of the end for the City Hall post office.
New York has relatively little Second-Empire architecture, and there’s an argument to be made that the old post office could have been repurposed – including getting rid of Mail Street – rather than demolished. But it was not well-loved and it was demolished in an era where such events happened all the time.