Flagg, who had also designed the previous, cast-iron, Art Nouveau style Singer Loft Building (built between 1902-1904) at 561 Broadway in SoHo, called the old building "Little Singer" to distinguish it from the new, expanded premises.

As early as in 1898 Flagg had suggested that only the lower parts of a tall building should be allowed to occupy the area of the whole plot, and that the tower should be restricted to one quarter of the plot area. With this building Flagg preceded the 1916 zoning regulations; its 47-storey slender tower rose from the top of the large building block below, allowing more sunlight to reach the street.

The building of foundations for the tower involved the use of sunken caissons, below-ground, pressurized excavation wells, to prevent water from seeping into the working area. During the construction that took one year and eight months, the extensive use of steel bracing enabled a simple, slender shaft of brick and limestone that was topped by a widened, highly decorated Beaux-Arts top with a domed roof and a lantern.

At 204 m it was the first building to exceed in height such old monuments as the Pyramid of Cheops, the Washington Monument and the towers of Cologne Cathedral, although it was still far from beating the Eiffel Tower -- despite the Singer officials shamelessly praising it as "the highest building in the world". (Although it indeed was the tallest building with continuous usable inner space -- and with a usable function other than letting people climb up and see far...) Also the Singer Building had an observatory facility at the top, on the 40th floor.

Even this size wasn't enough in 1968, when it was torn down -- as the tallest building in the world to be demolished -- because its replacement, the U.S. Steel Building eventually had five times more usable floor space.

The 213.5 m tall tower facing Madison Square Park was added to the original building (108,700 m², built in 1893) to make it the tallest in the world (the Woolworth Building, in turn, took the title four years later).

Modelled after the clock tower of St. Mark's Cathedral in Venice, this 50-storey tower also has bells atop -- four bronze bells, sounding off Händel every fifteen minutes during the day and the evening. The upper portion of the regularly fenestrated shaft sports an 8-meter diameter clock face on every facade. The pyramidal roof with its lantern top is lit at night.

Originally clad in marble facing, the facade material of the tower was replaced with limestone in a 1964 renovation by Lloyd Morgan, along with general simplification of the base decor.

The interior decor comprises 14 murals by painter Newell Covers Wyeth who was paid a generous $5 per square foot for his services...

Once also a warehouse for MetLife's archives, the 25100 m² tower is now used as office space.

In March 2005, SL Green Realty Trust bought the tower for $918 million with a residential conversion in mind. The air rights of the adjoining lower office portion are included in the deal, allowing the construction of another, 43,700 m² tower next to the original. In March 2006, the owners sold 70 percent of the tower's ownership to RFR and Ian Schrager, with the conversion due to follow at a later date.

The Depression, however, prevented from realizing such grandiose plans (photo). When work came to a halt in 1933, only 29 storeys of the original plan had been completed. That reflects in, for example, the 30 elevators available for as many floors. Although the massive size of the building was enabled by air-conditioning and lighting, the bow-tie shape was, nevertheless, devised to provide sorts of light-court to maximize the available natural light.

Two whole floors of the building were originally built with low ceilings and fitted with filing cabinets for Met Life's files. Later, the floor was torn from between these storeys and the space turned into a banking hall.

There are two lobbies, with the southern, at 11 Madison, going through the whole longer axis of the building. Decor of the three storey high space consists of a coffered ceiling as well as of pink granite floors and gold vein-veined marble walls.

The project started life in 1909 when Frank W. Woolworth bought the long-coveted tract of land on Broadway opposite City Hall Park and hired Cass Gilbert -- already a distinguished designer -- as architect; Gilbert urged his client to make the new headquarters the tallest building in the world. Woolworth, in turn, influenced by his travels to Europe, wanted his architect to design it in neo-Gothic style.

When denied a loan to finance the construction, Woolworth paid for the building from the company's income, in the end totalling $13.5 million in cash. After several redesigns, one higher than the other, finally to exceed the rivalling Metropolitan Life Tower, the foundations were laid in August 1911 and, at the rate of one and a half storeys a week, the 60-storey building was completed two years later.

Rising from a 27-storey base, with limestone and granite lower floors, the tower is clad in white terra-cotta and capped with an elaborate set-back Gothic top, with the spire rising to the height of 241.5 m. It was to be the tallest building in the world for 17 years, until the 40 Wall Street exceeded its height.

The building boasts a highly decorated, three-storey marble lobby in the plan form of a latin cross, with semicircular arches, bronze ornaments and sculpted corbels on the walls (one of which represents Mr. Woolworth himself counting his dimes) and the vaulted ceiling decorated with glass mosaic in Byzantine style. No wonder the building was dubbed the "Cathedral of Commerce."

The building was opened in April 1913 with a gala for 800 persons, and the building's lights were switched on by President Wilson from the White House in Washington, D.C..

In 1980 the building exterior was restored to its original splendour, an assignment that cost more than the original construction work.

The Woolworth chain eventually went out of business and its successor, the Venator Group, sold the building to the Witkoff Group for $155 million in June 1998.

The NY University's School of Continuing and Professional Studies will expand to the first three office floors of the building (8,700 m²), with a separate entrance lobby on Barclay Street, equipped with new escalators. Also the top half of the building is facing new use, the space being converted into 145 luxury condominiums, designed by Costas Kondylis.

After two inconclusive design competitions to replace the City Hall in 1888 and 1893, and after a law was signed that prohobited the replacement of the old City Hall in 1894, the site of the 1907 competition was shifted to a plot to the north-east, originally meant for an extension of the Brooklyn Building trolley terminal.

The selection was made in 1908 and the next year work on this behemoth with 60,400 m² of office space -- a feature that helped the design to win the competition -- was begun. The first occupants moved to the building in January 1913, two years before work on it was completed.

The building was influenced by the fashionable "City Beautiful" movement of the 1890s which promoted plans for creating public buildings in landscaped parks. The mid-part of the 25-storey tripartite facade is a U-shaped mass of austere light-toned granite over a high colonnade that forms the building's base and separates a front yard from the sidewalk. The top portion of the building features a colonnade of Corinthian columns and pilasters.

The 16-storey top, above the middle section of the building, consists of a set-back tiered lantern on top of a square base, flanked by four smaller pinnacle turrets, symbolizing the four boroughs joined to Manhattan. At the height of 177 m stands the 6 m high statue Civic Fame by Adolph A. Weinman, New York City's second largest statue after the Statue of Liberty.

This building impressed Josif Stalin so much that the Moscow University main building (1949-1953) was later based on it -- as well as, in general, the whole grandiose public building style in the Soviet Union.

The building has an entrance to the Chambers Street subway station (1915), the first of many such connections to come. An archway leads through the mid-facade (a closed portion of Chambers St.) to the Police Headquarters across the landscaped Police Plaza.

The building was landmarked in 1966.

Occupying its whole plot, the 60,700 m² building rises perpendicularly for 33 stories and the south facade is recessed in the middle to allow in more natural light.

The windows are grouped in series of four throughout and the building is topped at 129 m with massive cornices of green colour.

The building underwent a $14 million renovation in 1986.

The neo-Renaissance office tower is clad in white terra-cotta tiles, with arched triple windows rising the height of the 24-storey 42nd Street facade. There are four corner terraces flanking the cruciform top floor which is covered by a similarly cruciform hipped roof and a flagpole.

At the time of its completion, the 107 m tall building was the tallest in NYC north of the Metropolitan Life Insurance Company Tower near Madison Square.

With its immediate Times Square surroundings undergoing drastic changes in form of renovation, alterations and new construction, the building has been retained as a 42nd Street landmark, with appropriately, the 41st Street entrance sporting a large canopy proclaiming the ground-floor space as a "McDonald's".

In August 2002, the 20,000 m² building was put on the auction block, it being expected to yield around $80 million.

The building was in fact made to the second plans for a skyscraper to the site: in 1908 Daniel H. Burnham (designer of the Flatiron Building) had designed a 62-storey tower of 323 m, but the project was postponed, and after the old company headquarters had burned down in 1912 -- and steps behind the scenes taken -- eventually, the 166 m tall design by Ernest R. Graham was built.

The neo-Renaissance building occupies the whole block, and rising in two masses above the base and connected by a wing for the building's whole height, forms a giant letter "H" when viewed from above.

The height of the building was decided upon after consulting with elevator engineer Charles Knox, who determined the optimum number of floors for effective elevator service in the building. This resulted in reducing the number of floors from the originally planned over 40 to 36. This was one of the first buildings where the number of floors in a skyscraper was determined by such calculations.

At the time of its completion, the building caused resentment due to its massive scale (housing over 111,000 m² of office space, a FAR equivalent of 30!), and for blocking sunlight from the street. The outrage subsequently led to the restriction of continuous vertical growth of tall buildings by the introduction of the 1916 zoning regulations by city authorities. An indication of the bulk of the building was the fact that it remained the largest office building (by internal volume) in the world until the Empire State Building of 1931.

The through-block entrance lobby has a pink marble floor, sandy-coloured marble walls and a vaulted, coffered ceiling. The building with its 5,000 windows once housed the exclusive Bankers Club on its top three floors.

The 29-storey building housed not only offices for various manufacturer and goods trader firms, but also acted as a haunt for executives with its heavily decorated clubroom and restaurant.

The building site is only 15 m wide and 27.5 m deep, and the architects remarked that they wanted to make the building "a model for the tall, narrow building in the center of a city block." And it was regarded as such for the next decade of feverish urban construction.

The style of the building follows the "traditional" early skyscraper style with its Gothic appearance -- English this time. On the side facaces, trompe l'oeil brickwork creates vertical "ribs" with a fake "shade" pattern to enhance the verticality. The windows are concentrated to the north and south facades, as well as to a recessed mid-facade light-well on the east facade.

At 146 meters, a set-back top houses the top floor with its high arched windows for Bush's personal offices as well as the water tower.

The interior decor comprised of extensive oak panelling, oriental carpets and antique furniture.

The building was acquired in the 1980s by the Lebanese Dalloul family's American Properties.

In 2002, plans for a sister building immediately to the west were publicized. In a design by Gruzen Samton, a 23-storey glass tower would be separated by a 15 cm gap -- necessitated by the earthquake codes -- bridged over on every floor to double the original building's space.

Along with the primary developer August Heckscher, a philanthropist and failed advocate of low-income housing programmes, also the architect, Charles A. Wetmore was investing on the building himself.

This mixed-use building was the first office deveopment resulting from the 1916 zoning variation. The 26-storey building's lower part follows the existing property and roof lines of the low-rises, after which it sets back to the French Renaissance tower with an octagonal pyramid roof and a tall chimney, both with gilded details. The rooster figure at the top was removed in 1942, to be melted for the war effort.

The barrel-vaulted lobby was built small to maximize the retail space, especially profitable in this area of Midtown.

The then Met apprentice, Museum of Modern Art, opened its first exhibition spaces here in 1929 (today, they have more boasting surroundings, also in tower architecture).

The neo-Classical building was constructed in stages to fill the southern portion of the block and the Broadway facade follows the street's curvature. The tower, with its stepped pyramidal roof above a colonnaded top, is at an oblique angle to the rest of the building, aligned with the island's regular grid.

The lobby, lined with pilasters and columns, sports the names of the founders of the oil company, including John D. Rockefeller. The Standard Oil Clock shows hours with the letter 'S' and minutes with the 'O'.

The building was vacated by the Standard Oil in 1956, when the company moved to the Socony-Mobil Building in Midtown.