In architecture, a “wedding-cake style” is an informal reference to buildings with many distinct tiers, each set back from the one below, resulting in a shape like a wedding cake, and may also apply to buildings that are richly ornamented, as if made in sugar icing.

In Italy, the Monument to Vittorio Emanuele II is in “wedding cake style”.
The British wedding-cake style was created by Sir Christopher Wren, who often placed a steeple at the top of a series of classically details diminishing lower stages (illustration), as with St. Paul’s Cathedral.
In the United States, the style has been predominant in New York City, thanks to the 1916 Zoning Resolution, a former zoning code which forced buildings to reduce their shadows at street level by employing setbacks, resulting in a ziggurat profile. The dome of the United States Capitol in Washington, D.C. is also described as being of wedding-cake style.
In Russia, the wedding-cake style supercharged with boldly scaled classical detailing is a typical feature of Stalinist architecture.

History and examples
In 1916, the first zoning resolution for New York City came into force in Manhattan , with the aim of curbing the arbitrarily high and narrow construction of high-rise buildings. Legislators considered it appropriate to provide people on the street with enough fresh air and sunlight. The most daunting example was the 1915 completed 40-story Equitable Building (New York) , whose four outer edges reach to the top in 164 meters height. Instead of adopting a general ban on new skyscrapers, the new law required buildings to be provided with setbacks above a certain height. With that they got the staircase structure of a wedding cake.

Only the construction boom of the 1930s after the Great Depression brought the wedding cake architecture to a breakthrough. It was no longer perceived as a blemish, but as a stylistic device. At that time, among other things, the Empire State Building with five striking gradations was created.

Although the term is closely related to Manhattan and led there to its own, today shaping the city skyscraper top aesthetics, one also speaks in the broader sense of the Monumento a Vittorio Emanuele II in Rome and St Paul’s Cathedral in London of wedding cakes. Closer to the original American are many buildings of Stalinist architecture, such as the Seven Sisters in Moscow.

As far-fetched, but occasionally mentioned in this context, is the ziggurat , which also tapers upwards, but usually has no clear stairs, but especially slopes.

Source From Wikipedia