Exterior The three exposed façades result from a long and complex evolution. Particularly in the thirteenth century, the exterior appearance of the church was radically altered: the patterned marble encrustation was added, and a multitude of columns with
cipollino marble shafts, and sculptural elements was applied to enrich the state church. It is probable that structural elements were also added to the façades or modified.
Western façade The exterior of the basilica is divided into two registers. On the western façade, the lower register is dominated by five deeply recessed
portals that alternate with large piers. In addition to the reliefs in the
spandrels, the sculpture at the lower level, relatively limited, includes narrow Romanesque bands, statues, and richly carved borders of foliage mixed with figures derived from Byzantine and Islamic traditions. The eastern influence is most pronounced in the
tympana over the northern-most and southern-most portals. The iconographic programme is expressed primarily in the mosaics in the lunettes. In the lower register, those of the lateral portals narrate the , the translation of Saint Mark's relics from Alexandria to Venice. From right to left, they show the removal of the saint's body from Egypt, its arrival in Venice, its veneration by the Doge, and its deposition in the church. This last mosaic is the only one on the façade that survives from the thirteenth century; the others were remade in the seventeenth, eighteenth, and nineteenth centuries. The general appearance of the lost compositions is recorded in Gentile Bellini's
Procession in Piazza San Marco (1496), which also documents the earlier
gilding on the façade. The intervening
aediculae with
pinnacles house figures of the
Four Evangelists and on the extremities, facing one another, the Virgin and the Archangel Gabriel in allusion to Venice's legendary foundation on the 25 March 421, the feast of the Annunciation. Culminating in the
Last Judgment over the main portal, the sequence of mosaics in the lateral lunettes of the upper register present scenes of Christ's victory over death: from left to right, the
Descent from the Cross, the
Harrowing of Hell, the
Resurrection, and the
Ascension. The reliefs of Christ and the Four Evangelists, now inserted into the northern façade, may also survive from the original decoration of the central lunette. The
four gilded bronze horses were among the early spoils brought from Constantinople after the Fourth Crusade. They were part of a
quadriga adorning the
Hippodrome and are the only equestrian team to survive from
classical Antiquity. In the mid-thirteenth century, they were installed prominently on the main façade of St Mark's as symbols of Venice's military triumph over Byzantium and of its newfound imperial status as the successor of the Byzantine Empire. Since 1974 the original four horses are preserved inside, having been substituted with copies on the balcony over the central portal.
Northern façade The aediculae on the northern façade contain statues of the four original Latin
Doctors of the Church:
Jerome,
Augustine,
Ambrose, and
Gregory the Great.
Allegorical figures of
Prudence,
Temperance,
Faith, and
Charity top the lunettes.
Southern façade The Gothic crowning continues in the upper register of the southern façade, the lunettes being topped with the allegorical figures of
Justice and
Fortitude and the aediculae housing statues of
Saint Anthony Abbot and
Saint Paul the Hermit. The southern façade is the most richly encrusted façade with rare marbles, spoils, and trophies, including the so-called pillars of Acre, the
statue of the four tetrarchs embedded into the external wall of the treasury, and the
porphyry imperial head on the south-west corner of the balcony, traditionally believed to represent
Justinian II and popularly identified as
Francesco Bussone da Carmagnola. After a section of the narthex was partitioned off between 1100 and 1150 to create an entry hall, the niche that had previously marked the southern end of the narthex was removed, and the corresponding arch on the southern façade was opened to establish a second entry. Like the entry on the western façade, the passage was distinguished with precious porphyry columns. On either side,
couchant lions and
griffins were placed. Presumably, the southern entry was also flanked by the two carved pillars long believed to have been brought to Venice from the Genoese quarter in St Jean d'Acre as booty of
the first Venetian–Genoese war (1256–1270) but actually spoils of the Fourth Crusade, taken from the
Church of St Polyeuctus in Constantinople. Between 1503 and 1515, the entry hall was transformed into the funerary chapel of
Giovanni Battista Cardinal Zen, bishop of Vicenza, who had bequeathed a large portion of his wealth to the Venetian Republic, asking to be entombed in St Mark's. The southern entrance was consequently closed, blocked by the altar and a window above, and although the griffins remain, much of the decoration was transferred or destroyed. The pillars were moved slightly eastward.
Entry hall (Zen Chapel) The decoration of the southern entry hall to the church was redone in the thirteenth century in conjunction with work in the adjoining narthex; of the original appearance of the entry hall, nothing is known. The present mosaic cycle in the barrel vault forms the prelude to the mosaic cycle on the main façade, which narrates the translation of Saint Mark's relics from Alexandria in Egypt to Venice. The events depicted include the , the angelic prophecy that Mark would one day be buried in Venice, which affirms Venice's divine right to possess the relics. The authority of Saint Mark is demonstrated in the scenes that show the writing of
his Gospel which is then presented to Saint Peter. Particular relevance is also given to the departure of Saint Mark for Egypt and his miracles there, which creates continuity with the opening scene on the façade, depicting the removal of the body from Alexandria. Although largely redone in the nineteenth century, the apse above the doorway that leads into the narthex probably maintains the overall aspect of the decoration from the first half of the twelfth century with the Virgin flanked by angels, a theme common in middle-Byzantine churches.
Interior Although St Mark's was modelled after the Church of the Holy Apostles in Constantinople, ceremonial needs and limitations posed by the pre-existing walls and foundations made it necessary to adapt the design. The cruciform plan with five domes was maintained. However the Holy Apostles was a true centrally planned church: the central dome, larger than the others, was alone pierced with windows, and the altar was located underneath. There was no distinction between the four crossarms: no apse existed and double-tiered arcades surrounded the interior on all sides. In contrast, the longitudinal axis was emphasized to create a space appropriate for processions associated with state ceremonies. Both the central and western domes are larger, accentuating the progression along the nave, and by means of a series of increasingly smaller arches, the nave visually narrows towards the raised chancel in the eastern crossarm, where the altar stands. As with the Holy Apostles, each dome rests on four barrel vaults, those of the central dome rising from quadripartite (four-legged) piers. But the two-tiered arcades that reinforced the vaults in the Holy Apostles were modified. In St Mark's there are no upper arcades, and as a result the aisles are less isolated from the central part of the church. The effect is of more unified sense of space and an openness that have parallels in other Byzantine churches constructed in the eleventh century, an indication that the chief architect was influenced by middle-Byzantine architectural models in addition to the sixth-century Church of the Holy Apostles.
Chancel and choir chapels The chancel is enclosed by a
Gothic altar screen, dated 1394. It is surmounted by a bronze and silver
Crucifix, flanked by statues of the Virgin and Saint Mark, together with the Twelve Apostles. On the left of the screen is the
ambo for readings from Scripture, while the on the right is the platform from which the newly elected Doge was presented to the people. Behind, marble banisters mark the limit of the choir, which after the reorganization by Doge Andrea Gritti () was utilized by the Doge, civic leaders, and foreign ambassadors. Prior to the sixteenth century, the Doge's throne was located near the choir chapel of
Saint Clement I, whose doorway opened to the courtyard of the Doge's Palace. The chapel was reserved for the Doge's private use. From the window above, which communicates with his private apartments, it was also possible for the Doge to assist at mass in the church. The tribunes on either side of the chancel are faced with bronze reliefs that portray events in the life of Saint Mark and his miracles. Beyond the banisters is the presbytery, reserved for the clergy, with the high altar which since 1835 contains the relics of Saint Mark, previously located in the crypt. The
altarpiece, originally designed as an
antependium, is the
Pala d'Oro, a masterpiece of
Byzantine enamels on gilded silver. The two choir chapels, located on either side of the chancel, occupy the space corresponding to the lateral aisles in the other crossarms. They are connected to the chancel through archways which also serve to reinforce the barrel vaults supporting the dome above. The choir chapel on the northern side is dedicated to Saint Peter. Historically, it was the principal area for the clergy. The mosaic decoration in the vaults above the chapels largely narrates the life of Saint Mark, including the events of the . They constitute the oldest surviving representation of the transfer of Saint Mark's relics to Venice.
Side altars and chapels The side altars in the transept were used primarily by the faithful. In the northern crossarm, the altar was originally dedicated to Saint John the Evangelist: the mosaics in the dome above show the aged figure of Saint John, surrounded by five scenes of his life in
Ephesus. The stone relief of Saint John, placed on the eastern wall of the crossarm in the thirteenth century, was later moved to the northern façade of the church, probably when the altar was rededicated in 1617 to the
Madonna Nicopeia, a venerated Byzantine icon from the late-eleventh/early-twelfth century. The date and the circumstances of the icon's arrival in Venice are not documented. Most likely one of many sacred images taken from Constantinople at the time of the Latin Empire, it was deposited in St Mark's treasury, with no specific importance associated. It began to acquire significance for the Venetians in the fourteenth century when it was framed with Byzantine enamels looted from the Pantokrator in Contantinople. At that time, it may have been first carried in public procession to invoke the Virgin's
intercession in ridding the city of the
Black Death. The icon acquired a political role as the
palladium of Venice in the sixteenth century when it came to be identified as the sacred image that had been carried into battle by various Byzantine emperors. In 1589, the icon was transferred to the small Chapel of Saint Isidore where it was made accessible to the public, and subsequently it was placed on the side altar in the northern crossarm. It was first referred to as the Madonna Nicopeia (
Nikopoios, Bringer of Victory) in 1645. The altar was rededicated in 1617 to the
True Cross, and since 1810, it has been the Altar of the
Blessed Sacrament. The long-neglected relics of Saint
Isidore of Chios, brought to Venice in 1125 by Doge
Domenico Michiel () on return from his military expedition in the
Aegean, were rediscovered in the mid-fourteenth century, and upon the initiative of Doge
Andrea Dandolo (), the Chapel of Saint Isidore was constructed between 1348 and 1355 to house them. An annual feast (16 April) was also established in the Venetian liturgical calendar. The Mascoli Chapel, utilized by the homonymous
confraternity after 1618, was decorated under Doge
Francesco Foscari () and dedicated in 1430. Against the piers that support the central dome, on either side of the chancel, Doge
Cristoforo Moro () erected at his personal expense two altars dedicated to Saint Paul and Saint James. The pier behind the Altar of Saint James is where the relics of Saint Mark are said to have been rediscovered in 1094: the miraculous event is depicted in the mosaics on the opposite side of the crossarm.
Baptistery The date of construction of the baptistery is not known, but it is likely to have been under Doge
Giovanni Soranzo (), whose tomb is located in the baptistery, an indication that he was responsible for the architectural adaptation. Similarly entombed in the baptistery is Doge
Andrea Dandolo who carried out the decorative programme at his personal expense. The mosaics present scenes from the life of Saint John the Baptist on the walls and, in the ante-baptistery, the infancy of Christ. Directly above the bronze font, designed by Sansovino, the dome contains the
dispersion of the Apostles, each shown in the act of baptizing a different nationality in reference to Christ's command to preach the Gospel to all people. The second dome, above the altar, presents Christ in glory surrounded by the
nine angelic choirs. The altar is a large granite rock, which according to tradition was brought to Venice from Tyre following the
Venetian conquest. It is said to be the rock upon which Christ stood to preach to the people of Tyre.
Sacristy In 1486,
Giorgio Spavento, as
proto (consultant architect and buildings manager), designed a new
sacristy, connected to both the presbytery and the choir chapel of Saint Peter; the location of the earlier sacristy is not known. It was Spavento's first project and the only one he oversaw to completion. Decoration began in 1493. The cabinets, used for storing
reliquaries,
monstrances,
vestments, and liturgical objects and books, were inlaid by
Antonio della Mola and his brother Paolo and show scenes from the life of Saint Mark. The mosaic decoration of the vault, depicting Old-Testament prophets, was designed by
Titian and executed between 1524 and 1530. Behind the sacristy is the church, also by Spavento, dedicated to Saint Theodore, the first patron saint of Venice. Constructed between 1486 and 1493 in an austere Renaissance style, it served as the private chapel for the
canons of the basilica and, later, as the seat of the
Venetian Inquisition.
Influence As the state church, St Mark's was a point of reference for Venetian architects. Its influence during the
Gothic period seems to have been limited to decorative patterns and details, such as the portal and painted wall decoration in the Church of
Santo Stefano and the portal of the Church of the
Madonna dell'Orto, consisting of an ogee arch with flame-like relief sculpture reminiscent of the
crockets on St Mark's. In the early Renaissance, despite the introduction of classical elements into
Venetian architecture by Lombard stonecutters, faithfulness to local building traditions remained strong. In the façades of
Ca' Dario and the Church of
Santa Maria dei Miracoli, surface decoration in emulation of St Mark's is the principal characteristic, and the overall effect derives from the rich encrustation of shimmering coloured marbles and the circular patterns, derived from the basilica. Similarly, the Foscari Arch in the courtyard of the Doge's Palace is based on ancient
triumphal arches but owes its detailing to the basilica: the
superimposed columns clustered together, the Gothic pinnacles, and the crowning statuary. At the
Scuola Grande di San Marco, the reference to St Mark's is made in the series of lunettes along the roofline which recalls the profile of the basilica. Venezia Chiesa di Santo Stefano Innen Langhaus Süd 2.jpg|alt=photo of lateral nave of Santo Stefano|Santo Stefano Madonna dell'Orto Portail.jpg|alt=photo of entry of Madonna dell'Orto|
Madonna dell'Orto Palazzo Dario Cropped.jpg|alt=photo of facade of Ca' Dario|
Ca' Dario Santa Maria dei Miracoli facciata sud Venezia notte.jpg|alt=photo of facade of Santa Maria dei Miracoli|
Santa Maria dei Miracoli Arc Foscari, pati del Palau Ducal de Venècia.JPG|alt=photo of Foscari Arch|Foscari Arch Scuola Grande di San Marco Ospedale di Venezia facciata.jpg|alt=photo of facade of the Scuola Grande di San Marco|
Scuola Grande di San Marco ==Mosaics==