Iranian architecture or Persian architecture (Persian: معمارى ایرانی, Memāri e Irāni) is the architecture of Iran and parts of the rest of West Asia, the Caucasus and Central Asia. Its history dates back to at least 5,000 BC with characteristic examples distributed over a vast area from Turkey and Iraq to Uzbekistan and Tajikistan, and from the Caucasus to Zanzibar. Persian buildings vary from peasant huts to tea houses, and garden pavilions to "some of the most majestic structures the world has ever seen". In addition to historic gates, palaces, and mosques, the rapid growth of cities such as the capital Tehran has brought about a wave of demolition and new construction.
Iranian architecture displays great variety, both structural and aesthetic, from a variety of traditions and experience. Without sudden innovations, and despite the repeated trauma of invasions and cultural shocks, it has achieved "an individuality distinct from that of other Muslim countries". Its paramount virtues are: "a marked feeling for form and scale; structural inventiveness, especially in vault and dome construction; a genius for decoration with a freedom and success not rivaled in any other architecture".
Traditionally, the guiding formative motif of Iranian architecture has been its cosmic symbolism "by which man is brought into communication and participation with the powers of heaven". This theme has not only given unity and continuity to the architecture of Persia, but has been a primary source of its emotional character as well.
According to American historian and archaeologist Arthur Pope, the supreme Iranian art, in the proper meaning of the word, has always been its architecture. The supremacy of architecture applies to both pre- and post-Islamic periods.
Traditional Persian architecture has maintained a continuity that, although temporarily distracted by internal political conflicts or foreign invasion, nonetheless has achieved an unmistakable style. In this architecture, "there are no trivial buildings; even garden pavilions have nobility and dignity, and the humblest caravanserais generally have charm. In expressiveness and communicativity, most Persian buildings are lucid, even eloquent. The combination of intensity and simplicity of form provides immediacy, while ornament and, often, subtle proportions reward sustained observation."
Iranian architecture makes use of abundant symbolic geometry, using pure forms such as circles and squares, and plans are based on often symmetrical layouts featuring rectangular courtyards and halls.
Certain design elements of Persian architecture have persisted throughout the history of Iran. The most striking are a marked feeling for scale and a discerning use of simple and massive forms. The consistency of decorative preferences, the high-arched portal set within a recess, columns with bracket capitals, and recurrent types of plan and elevation can also be mentioned. Through the ages these elements have recurred in completely different types of buildings, constructed for various programs and under the patronage of a long succession of rulers.
The columned porch, or talar, seen in the rock-cut tombs near Persepolis, reappear in Sassanid temples, and in late Islamic times it was used as the portico of a palace or mosque, and adapted even to the architecture of roadside tea-houses. Similarly, the dome on four arches, so characteristic of Sassanid times, is a still to be found in many cemeteries and Imamzadehs across Iran today. The notion of earthly towers reaching up toward the sky to mingle with the divine towers of heaven lasted into the 19th century, while the interior court and pool, the angled entrance and extensive decoration are ancient, but still common, features of Iranian architecture.