The architectural plan

St. Mark’s church, begun in 1063, was built on the foundations and with the walls of an earlier church also dedicated to the saint. The model for this new church, much larger than the former one, was the Basilica of the Twelve Apostles in Constantinople.

The new structure was Greek cross with the longitudinal nave slightly longer than the transept limited by pre-existing buildings (the ancient castle to the south and the Church of St. Theodore to the north). The five great cupolas were erected at the intersection and over the arms of the cross.
The architectonic layout is highly articulated and repeats a single module clearly identifiable in the central cupola which rests, by means of the spandrels and great vaults, on four pillars. Both arms of the cross are divided into nave and two aisles.

The atrium with its cupolas was built a century after completion of the church. The baptistery was built onto the southern end of the church in the first half of the 14th century. Beneath the presbytery and the side chapels is the crypt (nave and two aisles with apse) housing the ancient chapel which for centuries has been the repository of St. Mark’s body.


The architectural idea underlying St. Mark’s Church is deeply rooted in the cultural context of Constantinople. The model was the Church of the Twelve Apostles, built in Justinian’s day and destroyed in 1462.
The present-day church was built on the remains of the first and second church in the space available between the Ducal Palace and the Church of St. Theodore (810-819). A bold solution which in the 11th century united memories – the tomb and its remains of St. Mark’s body – with the Greek cross plan of a great new church with five cupolas, the prestigious “Ducal Chapel“.
In St. Mark’s each cupola rests on four great vaults whose weight is borne by four pillars.
The interior has a unitary sequence subdivided into individual spatial orchestrations to which gold background mosaics ensure continuity and the church’s special way of being. Unlike the Greek models the altar, which is joined to the evangelist’s tomb, is not in the centre of the cross but beneath the eastern, presbytery cupola.
The church subsequently underwent substantial modifications: the narthex was added, a Gothic rosette was opened towards the Ducal Palace and the window of the horses opened in the facade, thus altering the atmosphere of the old building. Each modification was connected with structural, political or prestige reasons.


St. Mark’s church today is considered the living heritage of Roman, Byzantine and Venetian culture. It may be considered, ideally, as being enclosed in a quadrilateral space measuring almost 60 metres each side. The plan is Greek cross. Both arms of the cross are subdivided into nave and two aisles.
Beyond the transept, delimited by the iconostasis, the area of the eastern arm is occupied by the presbytery in the centre and, at the sides, by the chapels of St. Peter to the north and St. Clement to the south.
At the bottom of the presbytery, abutting the apse, there is an altar on a platform once raised by five steps, for deposition of the Most Holy. The transept extremities close with a rectilinear wall. To the north they take in the walls of the St. Isadore and Mascoli chapels, and to the south those of access to the Ducal Palace. On the west and north sides the church is surrounded by a narthex in which, at the southern end, there was the “sea gate”, now occupied by the chapel of cardinal Giovambattista Zen.

The main entrance from the west has a late 10th century wooden door faced with sheet copper and older bronze grilles. To right and left are the St. Clement and St. Peter entrances. At the northern end of the fa�ade, the St. Alipius entrance. In the northern arm the Door of Flowers is also closed with a bronze gate.
The church is accessed from the narthex by means of four doors: the central one, the St. Clement and the St. Peter, in correspondence to the chapels of the same name and, to the north the Door of the Virgin or of St. John.
The baptistery, built on the southern frontage at the limit of the sea gate, between the gate and an ancient corner-tower, features two cupolas and a vault connecting it to the structures of the Zen chapel. The tower, of uncertain function and transformed with the creation of the third St. Mark’s, is connected internally to the church and to the walls of the building incorporated into the head of the south transept. Today it houses the Treasure and the Sanctuary with the relics.
Access to the sacristy, enlarged at the end of the 15th century, is from the presbytery and St. Peter’s chapel. Adjacent to the sacristy there is the 15th century church of St. Theodore.

The nave and two aisle crypt with apse is beneath the presbytery and the side chapels. In the nave, beneath the high altar, there is the ancient chapel where the evangelist’s remains were kept. The crypt has an intersecting barrel-vault ceiling supported by small columns with simple basket-decorated Byzantine capitals datable to between the end of the 10th and the 11th centuries. To the west of the crypt, an area known as the “retro-crypt ” contains the tombs of all the patriarchs of Venice since 1807.

As a result of repeated fires the women’s galleries that covered the aisles of the west, north and south arms of the cross were eliminated. The only remaining women’s galleries are those above the wall structures: above the narthex, the chapel of St. Isadore, the palace boundary walls and the semi-domes of the apses in the chapels of St. Peter and St. Clement. All the rest have been reduced to simple passageways.

Two areas of the church may be defined: the ducal area in the south transept, closely connected with the palace by passages and windows at various levels, and the St. Mark’s primicerius’ and priests’ area in the north transept, linked to their respective lodgings. The height and size of the buildings around the church reduced the amount of light reaching the latter, so at the beginning of the 15th century the Serenissima decided to create two great openings: the window of the horses on the fa�ade and the rosette in the south transept overlooking the doge’s palace.

The cupolas – the Ascension in the centre, the Prophets over the presbytery, the Pentecost over the nave, the St. John over the north arm and the St. Leonard over the south arms of the transept consist of half-spheres in masonry standing on great support vaults. Around 1260 the masonry cupolas were covered by wooden ones of larger size topped with a small cupola bearing a gilded cosmic cross.
The wooden cupolas and the small cupola are dressed with 2-3 millimetre thick sheet lead.