The Pantheon (UK: /ˈpænθiən/, US: /-ɒn/;[1] Latin: Pantheum,[nb 1] from Ancient Greek Πάνθειον (Pantheion) '[temple] of all the gods') is an ancient 2nd century Roman temple and, since AD 609, a Catholic church (Italian: Basilica Santa Maria ad Martyres or Basilica of St. Mary and the Martyrs) in Rome, Italy.

The Pantheon was built on the site of an earlier temple, which had been commissioned by Marcus Vipsanius Agrippa during the reign of Augustus (27 BC – AD 14).

The Pantheon is a state property, managed by Italy's Ministry of Cultural Heritage and Activities and Tourism through the Polo Museale del Lazio.

[9] Cassius Dio, a Roman senator who wrote in Greek, speculated that the name of the Pantheon comes either from the statues of many gods placed around this building, or from the resemblance of the dome to the heavens.

Lise Hetland argues that the present construction began in 114, under Trajan, four years after it was destroyed by fire for the second time (Oros.

While more recent archaeological diggings have suggested that Agrippa's building might have had a circular form with a triangular porch, and it might have also faced north, much like the later rebuildings, Ziolkowski complains that their conclusions were based entirely on surmise; according to him, they did not find any new datable material, yet they attributed everything they found to the Agrippan phase, failing to account for the fact that Domitian, known for his enthusiasm for building and known to have restored the Pantheon after 80 AD, might well have been responsible for everything they found.

Ziolkowski argues that Lanciani's initial assessment is still supported by all of the finds to date, including theirs; he expresses scepticism because the building they describe, "a single building composed of a huge pronaos and a circular cella of the same diameter, linked by a relatively narrow and very short passage (much thinner than the current intermediate block), has no known parallels in classical architecture and would go against everything we know of Roman design principles in general and of Augustan architecture in particular.

[29] Cassius Dio, a Graeco-Roman senator, consul and author of a comprehensive History of Rome, writing approximately 75 years after the Pantheon's reconstruction, mistakenly attributed the domed building to Agrippa rather than Hadrian.

It has this name, perhaps because it received among the images which decorated it the statues of many gods, including Mars and Venus; but my own opinion of the name is that, because of its vaulted roof, it resembles the heavens.In 202, the building was repaired by the joint emperors Septimius Severus and his son Caracalla (fully Marcus Aurelius Antoninus), for which there is another, smaller inscription on the architrave of the façade, under the aforementioned larger text.

[30][31] This now-barely legible inscription reads: In English, this means: In 609, the Byzantine emperor Phocas gave the building to Pope Boniface IV, who converted it into a Christian church and consecrated it to St. Mary and the Martyrs on 13 May 609: "Another Pope, Boniface, asked the same [Emperor Phocas, in Constantinople] to order that in the old temple called the Pantheon, after the pagan filth was removed, a church should be made, to the holy virgin Mary and all the martyrs, so that the commemoration of the saints would take place henceforth where not gods but demons were formerly worshipped.

"[33] Twenty-eight cartloads of holy relics of martyrs were said to have been removed from the catacombs and placed in a porphyry basin beneath the high altar.

However, Paul the Deacon records the spoliation of the building by the Emperor Constans II, who visited Rome in July 663: Remaining at Rome twelve days he pulled down everything that in ancient times had been made of metal for the ornament of the city, to such an extent that he even stripped off the roof of the church [of the blessed Mary], which at one time was called the Pantheon, and had been founded in honour of all the gods and was now by the consent of the former rulers the place of all the martyrs; and he took away from there the bronze tiles and sent them with all the other ornaments to Constantinople.Much fine external marble has been removed over the centuries – for example, capitals from some of the pilasters are in the British Museum.

It was supposed to be the final resting place for the Monarchs of Italy of the House of Savoy, but the Monarchy was abolished in 1946 and the authorities have refused to grant burial to the former kings who died in exile (Victor Emmanuel III and Umberto II).

[44][45] Mark Wilson Jones has attempted to explain the design adjustments by suggesting that, once the higher pediment had been constructed, the required 50-foot columns failed to arrive (possibly as a result of logistical difficulties).

They were floated by barge down the Nile when the water level was high during the spring floods, and then transferred to vessels to cross the Mediterranean Sea to the Roman port of Ostia.

At its thickest point, the aggregate is travertine, then terracotta tiles, then at the very top, tufa and pumice, both porous light stones.

[52] Finite element analysis of the structure by Mark and Hutchison[54] found a maximum tensile stress of only 0.128 MPa (18.5 psi) at the point where the dome joins the raised outer wall.

On Pentecost, huge quantities of red rose petals are thrown through the oculus by firefighters of the Vigili del Fuoco on the roof.

The overall effect is immediate viewer orientation according to the major axis of the building, even though the cylindrical space topped by a hemispherical dome is inherently ambiguous.

Enshrined on the apse above the high altar is a 7th-century Byzantine icon of the Virgin and Child, given by Phocas to Pope Boniface IV on the occasion of the dedication of the Pantheon for Christian worship on 13 May 609.

The first members were, among others, Antonio da Sangallo the younger, Jacopo Meneghino, Giovanni Mangone, Zuccari, Domenico Beccafumi, and Flaminio Vacca.

The institution still exists, and is now called the Academia Ponteficia di Belle Arti (The Pontifical Academy of Fine Arts), based in the palace of the Cancelleria.

The stucco relief on the left, Dream of St Joseph, is by Paolo Benaglia, and the one on the right, Rest during the flight from Egypt, is by Carlo Monaldi.

The third niche holds the mortal remains – his Ossa et cineres, "Bones and ashes", as the inscription on the sarcophagus says – of the great artist Raphael.

The sarcophagus was given by Pope Gregory XVI, and its inscription reads ILLE HIC EST RAPHAEL TIMUIT QUO SOSPITE VINCI / RERUM MAGNA PARENS ET MORIENTE MORI, meaning "Here lies Raphael, by whom the great mother of all things (Nature) feared to be overcome while he was living, and while he was dying, herself to die".

On the right side is the low relief Cardinal Consalvi presents to Pope Pius VII the five provinces restored to the Holy See (1824) made by the Danish sculptor Bertel Thorvaldsen.

[citation needed] As the best-preserved example of an Ancient Roman monumental building, the Pantheon has been enormously influential in Western architecture from at least the Renaissance on;[71] starting with Brunelleschi's 42-metre (138 ft) dome of Santa Maria del Fiore in Florence, completed in 1436.

[72] Among the most notable versions are the church of Santa Maria Assunta (1664) in Ariccia by Gian Lorenzo Bernini, which followed his work restoring the Roman original,[73] Belle Isle House (1774) in England and Thomas Jefferson's library at the University of Virginia, The Rotunda (1817–1826).

[77] The 1824 Henriette Wegner Pavilion in Oslo's famous Frogner Park features a painted miniature copy of the Pantheon dome.

[78] The Pantheon's dome was an inspiration for the Volkshalle, an assembly hall planned but never built by the Nazi German architect Albert Speer for Adolf Hitler's intended rebuilding of Berlin as "Germania".