the basilica of Saint John Lateran was built under pope Melchiade (311-314). It is the oldest surviving church in the world. Due to the fact that the pope is also the bishop of Rome, Saint John in Lateran is also Rome's Cathedral.
The present structure of the Basilica resembles the Saint Peter's basilica. The original plan had already five aisles. The ancient church was residence of the popes until the coming back from the exile in Avignone (1377), when it was moved to the Vatican. It was pillage-stock of the Visigoths (410), the Vandals (455); the earthquake in 896 caused the central aisle roof to collapse (rebuilt under pope Sergio III in 904-911).
Put on fire in 1308 first and in 1361 then, it was remade under the pontificate of Gregorio XI (1370-1378), following the plan of the ancient structure that had by then become a ruin. The repair works continued during the entire fifteenth century and the sumptuous ceiling was realized in 1562.
Sisto V (1585-1590) ordered the construction of the Blessings Lodge (positioned at the end of right side aisle), and the making of the Lateranense building assigning the project to Domenico Fontana.
After about 140 years Pope Innocenzo X Pamphili (1644-1655) decided in 1646 to bring the cathedral to new splendour entrusting Francesco Borromini of the repair. The architect was supposed to finish the works in time for the Holy Year of 1650 and had to reserve (according to the pacts with the pope) the structure of the ancient Basilica of St John Lateran. The artist put 12 niches spaced up by 5 huge arches supported by as many pillars in the mid aisle.
The great statues of the Apostles that we can admire today in the borrominian niches were made by sculptors of the late baroque in the beginning of 1700.
In 1731 Pope Clement XII summons a competition for the new façade of Saint John in Lateran. The winner without too much merit was the Florentine Alessandro Galilei who in 1735 finishes the works of the present façade. Under the ogival tabernacle (at the end of the central aisle, in the transept) is the papal altar where only the Pope can give mass. Above the sacramental altar there's a fragment of the table on which Jesus consumed the last supper. The Cathedral hosts also Jesus' blood, brought to Rome by centurion Longino. Numerous are the chapels of noble families realized by some of the best artists of the different epochs. In the intermediate right aisle, close to the first pillar, one can admire Boniface VIII proclaims the Jubilee of 1300, a fresco made by Giotto.References:
The Mosque–Cathedral of Córdoba, also known as the Great Mosque of Córdoba and the Mezquita is regarded as one of the most accomplished monuments of Moorish architecture.
According to a traditional account, a small Visigoth church, the Catholic Basilica of Saint Vincent of Lérins, originally stood on the site. In 784 Abd al-Rahman I ordered construction of the Great Mosque, which was considerably expanded by later Muslim rulers. The mosque underwent numerous subsequent changes: Abd al-Rahman II ordered a new minaret, while in 961 Al-Hakam II enlarged the building and enriched the Mihrab. The last of such reforms was carried out by Almanzor in 987. It was connected to the Caliph"s palace by a raised walkway, mosques within the palaces being the tradition for previous Islamic rulers – as well as Christian Kings who built their palaces adjacent to churches. The Mezquita reached its current dimensions in 987 with the completion of the outer naves and courtyard.
In 1236, Córdoba was conquered by King Ferdinand III of Castile, and the centre of the mosque was converted into a Catholic cathedral. Alfonso X oversaw the construction of the Villaviciosa Chapel and the Royal Chapel within the mosque. The kings who followed added further Christian features, such as King Henry II rebuilding the chapel in the 14th century. The minaret of the mosque was also converted to the bell tower of the cathedral. It was adorned with Santiago de Compostela"s captured cathedral bells. Following a windstorm in 1589, the former minaret was further reinforced by encasing it within a new structure.
The most significant alteration was the building of a Renaissance cathedral nave in the middle of the expansive structure. The insertion was constructed by permission of Charles V, king of Castile and Aragon. Artisans and architects continued to add to the existing structure until the late 18th century.
The building"s floor plan is seen to be parallel to some of the earliest mosques built from the very beginning of Islam. It had a rectangular prayer hall with aisles arranged perpendicular to the qibla, the direction towards which Muslims pray. The prayer hall was large and flat, with timber ceilings held up by arches of horseshoe-like appearance.
In planning the mosque, the architects incorporated a number of Roman columns with choice capitals. Some of the columns were already in the Gothic structure; others were sent from various regions of Iberia as presents from the governors of provinces. Ivory, jasper, porphyry, gold, silver, copper, and brass were used in the decorations. Marvellous mosaics and azulejos were designed. Later, the immense temple embodied all the styles of Morisco architecture into one composition.
The building is most notable for its arcaded hypostyle hall, with 856 columns of jasper, onyx, marble, granite and porphyry. These were made from pieces of the Roman temple that had occupied the site previously, as well as other Roman buildings, such as the Mérida amphitheatre. The double arches were an innovation, permitting higher ceilings than would otherwise be possible with relatively low columns. The double arches consist of a lower horseshoe arch and an upper semi-circular arch.