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Palladian style

Palladio is known as one of the most influential architects in Western architecture. His architectural works have "been valued for centuries as the quintessence of High Renaissance calm and harmony".

The basic elements of Italian Renaissance architecture, including Doric columns, lintels, cornices, loggias, pediments and domes had already been used in the 15th century or earlier, before Palladio. They had been skillfully brought together by Brunelleschi in the Pazzi Chapel (1420) and the Medici-Riccardi Palace (1444–1449). At the beginning of the High Renaissance in the early 16th century, Bramante used these elements together in the Tempietto in Rome (1502), which combined a dome and a central plan based on a Greek Cross. The architect Baldassare Peruzzi had introduced the first Renaissance suburban villas, based on a Roman model and surrounded by gardens. The Farnese Palace in Rome (1530–1580) by Sangallo introduced a new kind of Renaissance palace, with monumental blocks, ornate cornices, lateral wings and multiple stairways. Michelangelo had made a plan for a central dome at Saint Peter's Basilica and added a new loggia to the facade of the Farnese Palace. All of these plans already existed before Palladio; his contribution was to refine, simplify, and use them in innovative ways.

The style of Palladio employed a classical repertoire of elements in new ways. He clearly expressed the function of each part of the building by its form, particularly elevating and giving precedence to the piano nobile, the ceremonial floor, of his villas and palaces. As much as possible he simplified the forms, as he did at Villa Capra "La Rotonda", surrounding a circular dome and interior with perfectly square facades, and placing the building pedestal to be more visible and more dramatic.

Palladio was inspired by classical Roman architecture, but he did not slavishly imitate it. He chose elements and assembled them in innovative ways appropriate to the site and function of the building. His buildings were often placed on pedestals, raising them and making them more visible, and so they could offer a view. The villas very often had loggias, covered arcades or walkways on the outside of upper levels, which gave a view of the scenery or city below, and also gave variety to the facade. When he designed his rustic villas and suburban villas, he paid particular attention to the site, integrating them as much as possible into nature, either by sites on hilltops or looking out at gardens or rivers.

The Serlian window, or Venetian window, also known as a Palladian window, was another common feature of his style, which he used both for windows and the arches of the loggias of his buildings. It consists of an arched window flanked by two smaller square windows, divided by two columns or pilasters and often topped by a small entablature and by a small circular window or hole, called an oculus. These particular features originally appeared in the triumphal arches of Rome, and had been used in the earlier Renaissance by Bramante, but Palladio used them in novel ways, particularly in the facade of the Basilica Palladiana and in the Villa Pojana. They also became a common feature of later Palladian buildings in England and elsewhere.

In his later work, particularly the Palazzo Valmarana and the Palazzo del Capitaniato in Vicenza, his style became more ornate and more decorative, with more sculptural decoration on the facade, tending toward Mannerism. His buildings in this period were examples of the transition beginning to what would become Baroque architecture.