San Marco is a minor basilica in Rome dedicated to St. Mark the Evangelist. It was first built in 336 by Pope Mark, whose remains are in an urn located below the main altar. The basilica is the national church of Venice in Rome.
After a restoration in 792 by Pope Adrian I, the church was rebuilt by Pope Gregory IV in 833. Besides the addition of a Romanesque bell tower in 1154, the major change in the architecture of the church was ordered by Pope Paul II in 1465-70, when the façade of the church was restyled according to the Renaissance taste with a portico and loggia, using marbles taken from the Colosseum and the Theatre of Marcellus. The façade is attributed to Leon Battista Alberti. Paul II being a Venetian by birth, assigned the church to the Venetian people living in Rome.
The last major reworking of the basilica was started in 1654-57 and completed by Cardinal Angelo Maria Quirini in 1735-50. With these restorations, the church received its current Baroque decoration.
The floor of the church is below the ground level of the Renaissance period, and therefore steps lead down to the interior. The church retains its ancient basilica format, with a raised sanctuary. The inside of the church is clearly Baroque. However, the basilica shows noteworthy elements of all her earlier history:
the apse mosaics, dating to Pope Gregory IV (827-844), show the Pope, with the squared halo of a living person, offering a model of the church to Christ, in the presence of Mark the Evangelist, Pope Saint Mark and other saints. The wooden ceiling, with the emblem of Pope Paul II (1464-1471), is one of only two original 15th-century wooden ceilings in Rome, together with the one at Santa Maria Maggiore.
In the portico are several early Christian grave stones, as well as the gravestone of Vannozza dei Cattanei, the mistress of Cardinal Rodrigo Borgia.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.