San Marcello al Corso is a 16th century conventual and titular church on 4th century foundations with a postal address at Piazza San Marcello 5 in the rione Trevi. Pictures of the church at Wikimedia Commons are here. There is an English Wikipedia page here.
The dedication is to Pope St Marcellus.
This church is not a minor basilica.
The historical importance of Pope Marcellus (308-9) as regards the churches of Rome is that the Liber Pontificalis credits him with the arrangement of the territory of the city into twenty-four tituli. This amounted to the inauguration of the parochial system, and was in the context of a renewal of the Church after the great persecution of Diocletian. However the pagan emperor Maxentius sent the pope into exile very soon after this, and he quickly died in unknown circumstances. His body was brought back, and buried in the basilica of San Silvestro a Priscilla. Maxentius himself, the last emperor to be permanently resident at Rome, was defeated by Constantine at the Battle of the Milvian Bridge.
The legend of the church's foundation as we now have it derives from the Passio Marcelli, which was composed in the 5th century and is dubiously historical. According to the developed mediaeval version, Maxentius thought that the Christian religion was horse-shit and so thought it appropriate to condemn Pope Marcellus to work as a slave in the city terminus of the department of the Cursus Publicus operating on the Via Flaminia. The city end of this road was the Via Lata, the present Corso, and the so-called catabulum (an unfamiliar Latin word) had very large stables used by lots of horses. The pope had to clean these out with his bare hands (incredibly, the ancient Romans never managed to invent the wheelbarrow), and died as a result of nausea induced by the stink. After Maxentius was overthrown, the city's Christians then converted the stables into a basilica in the pope's memory.
The circumstances of his martyrdom mean that St Marcellus has an informal status as a patron of paralegals.
An alternative version of the legend has the pope suffering one stint in the stables, then being freed and taking refuge in the house of the Roman lady Lucina, the foundress of the nearby church of San Lorenzo in Lucina. He was then re-arrested and put back in the stables to die, but it was Lucina's house that then became the basilica not the stables.
Documented early historyEdit
The first documentary evidence for the church is when Pope Boniface I was consecrated here in 418. This is because the supporters of a rival had occupied the Lateran. It was then listed in the surviving acts of a Roman synod in 499 as the Titulus Marcelli, also in 595. Modern scholars are uneasy about automatically equating the Marcellus of this titulus with the pope, as he might have been the original donor of the property instead.
The church was restored by Pope Adrian I (772-95). The relics of Pope Marcellus were brought from San Silvestro a Priscilla by Pope Gregory IV (827-44) and enshrined here; this was because the Catacomb of St Priscilla was being abandoned. The countryside outside the city walls was then regularly overrun by marauders, and visiting the catacombs was no longer safe.
Archaeological evidence of first churchEdit
Parts of the original palaeochristian basilica have been excavated by digging a little network of passages under the church, and the archaeological evidence thus gained is unusually informative.
The first thing to remember is that the original basilica was oriented in an opposite direction to the church there now. The façade was on the present Via di San Marcello (it is unknown as to whether there was an atrium), and the apse was under the present frontage on the Corso. There was originally a nave with side aisles (the archaeologists looked for the pier footings of the arcades but did not find them), and a large semi-circular apse. The latter was re-used at the church's establishment in the late 4th or early 5th century, by converting an earlier structure. It had been built in opus listatum, a building technique involving courses of brick interspersed with others in tufa stone, and had been revetted in decorative polychrome marble on the inside. Also, the curve of the apse contained a series of little columns which might have supported an apse vault.
The side aisle walls that were uncovered were constructed as new when the church was founded, and their interiors had been frescoed. Numerous fragments of painted plasterwork were found in the excavation, dating to about the year 400. The southern wall (then left hand side, now right hand side) showed evidence of a later decorative scheme of about the 7th century, involving fresco work imitating draped fabric.
Flooring of the two side aisles was also uncovered, dating from after the foundation of the church. Patches of brick flooring in a herringbone pattern were found in the north aisle, but the south aisle turned up an area of flooring in opus sectile marble work dating from the 6th or 7th centuries. This involved rays of green serpentine running from central discs of red marble, the sectors in between the rays being filled in with roughly square fragments of variously coloured marbles poorly laid in a semi-random manner. This floor was later repaired very crudely by having fragments of broken-up marble tomb slabs used to patch it.
There was a separate baptistery to the north of the basilica, which was excavated in 1912. It was installed in a pre-existing building in the 5th century, and was a plunge-pool which was circular outside and hexagonally polylobate within. The floor of the baptistry was raised in the early Middle Ages and a new font put on top of the old one, of identical design.
By the 11th century the church was parochial and collegiate, being administered by a college of secular priests.
The archaeology gives evidence of two major structural interventions in the 12th century. Firstly, in the middle of that century the north side aisle (and presumably the south one also, although evidence was not found) was provided with a small apse at its far end next to the sanctuary apse. The floor was laid in Cosmatesque style, and the wall of the side-apse and the aisle near it was frescoed in palm trees and with a surviving figure of St Martin of Tours. The little apse might have been a chapel dedicated to him.
The next intervention was at the end of the century, when the new side-apses were demolished together with the main apse and replaced by a large transept with little apses at its ends.
In 1354, the body of Cola di Rienzo was brought here three days after he had been killed in front of the steps leading to Santa Maria in Aracoeli, and hung up in the apse. Then it was given to the Jews of the city to be burned by them.
Fire and rebuildingEdit
A fire on the night of 22 May 1519 completely destroyed the church. Apart from the outer walls, the only item that survived was a 15th century wooden crucifix which is now to be found in the Chapel of the Crucifix. The preservation of this crucifix was considered miraculous, and devotion to it increased enormously in 1522 when an epidemic stopped just when a penitential procession was held with it. These events led to the foundation of the Oratorio del Santissimo Crocifisso, built for a confraternity of the parish here and completed in 1568.
Money was collected by the Servites to rebuild the church, a work which began immediately to a design by Jacopo Sansovino who suggested re-orienting the church to make it face the Corso. Also, he abolished the transept and side aisles in favour of two ranges of side chapels which could be patronized by noble families in exchange for funerary rights. However, in 1527 the available funds had to be used to bribe the soldiers of Emperor Charles V so that they would not plunder the complex during the Sack of Rome. This event also caused the artists at work on the interior to flee, leaving their work unfinished. Sansovino himself went to Venice, where he was to have a flourishing career, and the friars sold their convent building so as to have funds to continue with the church.
Antonio Sangallo the Younger took over in 1529, only to suffer a setback in 1530 when the Tiber flooded the area. Six years later Giovanni Mangone was appointed to complete the project. Annibale Lippi designed and executed the apse in 1569, and then there was a pause in the work.
Meanwhile, the friars rebuilt their little convent in 1660.
The present façade was a separate project, designed by Carlo Fontana and built between 1682 and 1686. The church was then judged to be finished, and finally consecrated in 1592. The last interventions were the provision of the statues on the upper façade, done in 1701, and the erection of a campanile in 1703 by Carlo Francesco Bizzaccheri. These late works were the result of a benefaction by Roberto Orsini.
From 1861 to 1867 the interior was restored by Virginio Vespignani, especially the sanctuary.
In 1873 the Servite convent was sequestered by the Italian government, and for a time was a police law court for trying minor offences. The church, however, continued to be administered by the Servites, and in the early 20th century the convent was leased back to them. The Order's Generalate or headquarters now occupies the premises. The nearby parish church of Santa Maria in Via also belongs to the friars.
The traditional date of the founding of the titulus is 304, but the first cardinal priest listed was appointed in 1316.
The current titular of the church is Giuseppe Betori, Archbishop of Florence, who was appointed in 2012.
Layout and fabricEdit
The church is structurally a nave with aisles, of five and a half bays. The half-bay is at the entrance, and the far end is continued by a shallow rectangular presbyterium having a large apse both of the same height as the nave ceiling. The structural side aisles are divided into side chapels by blocking walls.
The architecturally separate façade is stuck onto the entrance frontage, and is substantially higher than the nave roof behind.
The original idea was to have a façade with two flanking campanili. However, this was abandoned and a single one was put over the convent next to the bottom right hand corner of the nave by Carlo Francesco Bizzaccheri in 1703.
It has an odd form. The south side, away from the church, has the aspect of a typical Baroque slab bellcote, with two arched soundholes side by side in the storey above the roofline. These have a bell in each, and are separated by a buttress. Above them is an almost square aperture for the smaller bells, flanked by a pair of incurved volutes in shallow relief and topped by a segmental pediment with a broken cornice and with the side slightly projecting.
The oddity lies in the north side, facing the church. Here, instead of the two arched soundholes the sides of the bellcote are extended to create a void with a very shallow curved top which contains no bells. The details above this are identical to those on the other side.
The coved (concave) late Baroque (tardobarocco) façade built 1682-1686 is by Carlo Fontana and is now considered one of his finest works. It was very influential at the time in
Italy and the German lands, and marks the transition from Middle Baroque to the late period. The architect was fairly faithful to Classical ideals of architecture, and it was partly owing to his influence that the Rococo style never became popular in Rome.
However, in the 19th century and for most of the 20th century it was fashionable to be rude about the work. Firstly the neo-Classical and then the early modernist ideologists condemned it, either for being incorrect or for being dishonest. Both architectural schools were notorious for lacking the sense of humour that the Baroque style displays, and for having their adherents suffer from what is technically known as reflexive intromission (that is, being up themselves).
There are two storeys, with the second storey and the entrance zone below that (which front the central nave) slightly projecting in front of the two side zones which mark the side aisles. The architectural order used for the pilasters and columns is Composite, and the work is entirely in travertine limestone. The entire façade is on a plinth, with the single entrance approached by a short flight of stairs.
A pair of pilasters in shallow relief define the outer corners of the first storey, and the side corners of the entrance zone. A further pair of doubletted pilasters is tucked into the inner corners created by the projection forward of this zone. Then, a pair of free-standing columns with their own plinths are placed in front of these doublets, and two pairs of identical columns (each pair sharing a plinth) are placed flanking the entrance. Pilasters and columns support the entablature dividing the storeys, which has a zig-zag profile as a result.
Above the section of entablature supported by the four entrance columns is a split segmental pediment intruding into the second storey, with the arcs made parabolic. Into the split is inserted a molded square stone frame, which looks as if it once contained a clock. This has its own triangular pediment.
Sculpture of first storeyEdit
The entrance doorcase is molded, and above it is a floating cornice. Above that in turn is a famous relief sculpture depicting St Philip Benizi Refusing the Tiara by Antonio Raggi, 1686, recalling the legend that the 15th century saint was elected pope but did not consider himself worthy of being the Vicar of Christ. The sculpture is in a molded tondo supported by a pair of lively and very realistic angels, and there is also a putto crawling over the top of the frame.
The side zones of this storey have a pair of statues of St Philip Benizi and Pope St Marcellus by Francesco Cavallini, 1686, in round-headed niches surmounted by crossed acanthus leaves tied with ribbon.
The second storey is on an attic plinth. It has chamfered outer corners corresponding to the design below, and in these chamfers stand a pair of columns. The main frontage of this storey has four pilasters flanking a large rectangular window (obscured by the "clock frame"), and over this is an arched tympanum with a molded archivolt containing a spray of acanthus.
Columns and pilasters support a triangular pediment, with its outer angles recessed. The tympanum of this (in Italian tympanon, although the word is confusingly and incorrectly used for a pediment) contains an eroded relief scupture of a heraldic shield.
One very unusual and engaging feature of this façade is that the second storey has side sweeps in the form of palm fronds; you would expect arcs or volutes.
Sculpture of second storeyEdit
Statues of Blessed Gioacchino Piccolomini (also known as Joachim of Siena) and Blessed Francesco Patrizi, another holy Servite of Siena, occupy the outer corners of the attic plinth. On the split pediment over the entrance sit allegories of Faith and Hope , looking cheerful. These statues were provided in 1703 and have been ascribed to Andrea Fucigna, but are now thought to be by Cavallini also.
The convent is the rather anonymous 17th century building on the right side of the piazza. The friars used to occupy the Palazzo Mellini on the left hand side, which was donated to them in 1490 by Cardinal Giovanni Michiel who had built it. However, in 1532 the friars sold it in order to replace the money they lost in the Sack of Rome. After that, they had to make do with a very cramped and narrow convent to the right of the church, with no cloister or garden. This they rebuilt in 1660.
The present doorway of the convent is worth inspecting. It is 15th century, but originally belonged to the Palazzo Mellini. When that was re-ordered in 1909, the doorcase was donated to the friars. It still bears a double epigraph commemorating the cardinal, although his coat-of-arms has been defaced.
The church has a single nave of five and a half bays, with five chapels on each side. The half bay is at the entrance, and used to have a pair of passages for side entrances. The right hand one led into the convent, but the left hand one was converted into an eleventh chapel in the later 20th century.
The interior decoration is very rich, with many frescoes (mostly of the 17th century) and much gilded stucco ornament. The overall colour scheme of the walls is white and gold.
The arches into the chapels form arcades on either side of the nave, having molded archivolts springing from Doric imposts and separated by gigantic ribbed Corinthian pilasters. The latter support an entablature running round the entire church, which has gilded acanthus scrolls on its frieze and fronded modillions (little brackets) supporting the cornice.
Above the cornice, the central nave side walls have large rectangular windows separated by fresco panels illustrating scenes of the Passion. This fresco cycle includes the large one of the Crucifixion (1613) on the counterfaçade, and two smaller ones above it. It is by Giovanni Battista Ricci of Novara.
The flat coffered wooden ceiling was executed from 1592 to 1594. It is in blue, red and gold and features symbols illustrating Our Lady's titles from the Litany of Loreto. The central coffer has a carved relief of the Immaculate Conception. The designer was Carlo Francesco Lambardi.
The superb pulpit was designed by Giovanni Mattia de Rossi, and executed by Carlo Torriani in 1673. The angel supporting it is by Pietro Paolo Naldini, of the school of Bernini.
Monuments at entranceEdit
At the bottom of the nave to the left of the entrance is a very impressive Renaissance double tomb. The lower reclining effigy is of Cardinal Giovanni Michiel, a nephew of Pope Paul II and a generous benefactor of the Servites. According to rumour he was poisoned by one of the Borgias in 1503. Below his effigy is a pile of books, an allusion to his extensive library which he donated to the friars. The upper reclining effigy is Bishop Antonio Orso (died 1511), the Cardinal's nephew.
The memorial was probably executed by Jacopo Sansovino, although there has been some doubt expressed about this. It was commissioned in 1520 by Jacopo Orso da Chioggia, a nephew of Bishop Orso.
The triumphal arch rests on a pier of gigantic piers, around the tops of which the entablature runs. The archivolt springs from the latter, and unusually has its keystone hidden by the nave ceiling. The spandrels have frescoes of King David, to the left, and Moses, to the right. At the apex is a tablet saying Laudate servi Domini, a quotation from the first line of Psalm 113 -"Praise, o servants of the Lord"- which is applied to the Servites whose choir is in the apse.
The frescoes on the arch are all by Ricci. The pilasters feature the four Latin Doctors of the Church: SS Augustine, Jerome, Ambrose and Gregory (they are helpfully labelled). The intrados of the archivolt has two cycles of fresco panels. The outer one has God the Father in the middle, flanked by the four Evangelists, while the inner one has five scenes from the early life of Our Lady. Left to right, they are Birth, Presentation at the Temple, Marriage to Joseph, Annunciation and VIsitation.
The sanctuary has one shallow bay with a barrel vault, and then an apse. The high altar is free-standing, with polychrome marble decoration but no altarpiece and was designed by Sebastiano Cipriano in 1725 (but altered in the 19th century). Beneath it is a cippus or marble memorial stone from the 3rd century. The front is decorated with 12th century opus sectile, and it protects the relics of Pope St Marcellus.
To either side of the altar are cantorie or opera-boxes for solo musicians, here cantilivered out on brackets and having their balustrades gilded.
The apse behind has its curve occupied by the choir stalls of the Servite friars, and at its far end is an enormous picture of The Apotheosis of Pope St Marcellus in an arched gilt frame which has Ionic columns. This work takes the place of the altarpiece, and was installed in the mid 19th century restoration when the apse was re-ordered. It is a free copy of a ceiling fresco in the sacristy by Giovanni Battista Ciocchi.
There is a pair of pedimented windows flanking it, and four frescoes of Servite saints. The conch of the apse has a tripartite fresco cycle by Ricci featuring Our Lady (left to right) The Dormition, The Coronation and The Assumption.
Chapel of the AnnunciationEdit
The first chapel on the right is dedicated to the Annunciation to Our Lady, with an altarpiece by Lazzaro Baldi. The split segmental pediment of the aedicule contains a 15th century fresco fragment of the Madonna and Child, set in a gilded glory with putti.
The large polychrome wooden Pietà dates to about 1700, although it must have been repainted.
The chapel vault is an example of the illusionistic ceiling painting called quadratura, by which you are fooled into thinking that the edifice extends higher than the actual ceiling. This example is by Tarquinio Ligustri, 1607.
Chapel of SS Digna and EmeritaEdit
The second chapel on the right is the Cappella Muti Bussi, and is dedicated to SS Digna and Emerita. These were two Roman virgin martyrs, whose relics were originally at the Catacomba di Commodilla (although only Emerita has any historical claim to being genuine). The relics are enshrined in a porphyry urn under the altar.
This chapel was re-fitted in 1725 by Francesco Ferrari. The altarpiece then provided depicts the martyrdom, and is by Pietro Andrea Barbieri 1727. The vault shows the Apotheosis of the two martyrs, and is by Ignazio Stern.
The side walls have a pair of spectacular matching Baroque memorials to Giovanni Antonio Muti and Maria Colomba Vincentini, both by Bernardino Cametti 1725. The deceased are shown as if kneeling in prayer at a prie-dieu draped in a billowing cloth. The latter is carved in orange marble.
Chapel of Our Lady of GracesEdit
The third chapel on the right is the Cappella della Madonna delle Grazie, which is the Cappella Grifoni and is nicknamed the Cappella Madonnina. It has a large cycle of frescoes of scenes from the life of the Blessed Virgin, by Francesco Salviati, 1563. The altarpiece is a small 14th century icon of the Madonna and Child set in a 15th century arched frame of white marble.
A memorial to Cardinal Thomas Weld (died 1837) and his daughter Mary Lucy is also in this chapel, as well as one to Mattia de Grifoni, 1567. The fine effigy, of the school of Michelangelo, was put on a new tomb chest in 1651.
Chapel of the CrucifixEdit
The fourth chapel on the right is dedicated to the famous 14th century crucifix that survived the 1519 fire, which allegedly contains a relic of the True Cross.
The original decoration was begun by Perin del Vaga, one of Raphael's pupils. At the Sack of Rome in 1527 he fled, and left the chapel unfinished. After peace had been restored, Daniele da Volterra completed the ceiling vault frescoes. They depict The Creation of Eve in the central panel, and The Four Evangelists in the two side panels. These latter have not survived well. The consensus is that del Vaga finished Eve, and had made a start on Mark and John on the left -which had to be finished by da Volterra. Then, del Vaga's design for Matthew and Luke on the right was executed in its entirety by da Volterra. The contribution of Pellegrino Tibaldi is debated.
The crucifix serves as the altarpiece. The aedicule has a pair of Composite columns in pink marble, and on the frieze of the entablature is an epigraph reading Huc me meus impulit ardor ("To this my zeal has impelled me"). The tabernacle is by Carlo Francesco Bizzaccheri, 1689. Note the great number of ex-voto offerings on the walls flanking the aedicule.
The crucifix used to be at the Oratorio del Santissimo Crocifisso, but was brought back here in the early 19th century. It is sometimes moved into the sanctuary for liturgical events. At times of special intercession, such as the inauguration of the Second Vatican Council, it is carried in procession through the streets. It has its own lay confraternity to encourage devotion to it, the Arciconfraternita del Santissimo Crocifisso di San Marcello.
Chapel of St Peregrine LazioziEdit
The fifth chapel on the right (the Cappella Paolucci) is dedicated to St Peregrine Laziosi, a patron of cancer sufferers (his name in Italian is Pellegrino). This is because he was miraculously cured of a cancer in his leg, an event depicted in the altarpiece by Aureliano Milani, 1725. The side wall paintings depicting scenes from the saint's life are also by him.
Chapel of St Philip BeniziEdit
The sixth chapel on the left is dedicated to St Philip Benizi, one of the greatest saints of the Servite Order. The altarpiece is by Pier Leone Ghezzi, and depicts St Juliana Falconieri Receiving the Servite Rule from St Philip Benizi. She was the foundress of the Servite nuns. In the background is St Alexis Falconieri.
The side wall frescoes are by Bernardino Gagliardi, 1652 and depict The Miracle of the Multiplication of the Loaves by St Philip and The Funeral of St Philip. Here is a monument to Ferdinando Dandini de Sylva, 1918 by Enrico Tadolini.
Chapel of St PaulEdit
The fifth chapel on the left is the Cappella Frangipani and is dedicated to St Paul. The altarpiece showing The Conversion of St Paul is by Federico Zuccari, 1566, and the side wall and vault frescoes are by his brother Taddeo Zuccari. The latter show scenes from the life of the saint, with his martyrdom in the crown of the vault, and the pilasters have the four Latin Doctors.
The chapel is famous for its set of six memorial busts of members of the Frangipani family. On the right, Muzio 1588, Lello 1604 and Roberto 1622 are all by Allessandro Algardi. On the left, Antonino 1546, Curzio 1555 and Mario 1569 are anonymous.
Chapel of Our Lady of SorrowsEdit
The fourth chapel on the left is dedicated to Our Lady of Sorrows, devotion to whom has been propagated by the Servite Friars throughout their history. This chapel was sumptuously re-fitted in the 18th century by Zanobi del Rosso; look up to see a mob of stucco angels and putti, hanging out on the pediment of the aedicule and the cornices of the side walls.
The vault fresco is by Antonio Bicchierai (1678-1766). It has an interesting subject -The Presentation of the Child Jesus at the Temple. The moment is depicted when St Simeon the Elder holds the Christ-Child, and predicts that a sword would pierce Our Lady's soul. Note the Solomonic columns in the background.
The altar aedicule has a pair of Corinthian columns in a brecciated light green marble, which looks like verde antico but is not. The altarpiece showing Our Lady of Sorrows is by Pier Paolo Naldini, and could do with a clean. Our Lady is shown with the figurative seven swords of sorrow, prophesized by Simeon in Luke's Gospel, and highlighting the key Marian devotion of the Seven Sorrows which the Servite Order so faithfully promulgated. Above the aedicule is an unusual window in yellow glass, etched with a pair of angels adoring the Eucharist.
The side walls have a pair of good-quality works by Domenico Corvi, 1763. They depict The Abandonment of the Baby Moses in the Reeds and The Sacrifice of Isaac.
Chapel of St Mary MagdalenEdit
The third chapel on the left is dedicated to St Mary Magdalen, and has an altarpiece by Girolamo Troppa depicting The Penitent Magdalen in the Desert. The skull that she is holding and her loose hair are typical attributes of this subject. Slightly unusual is that she is a brunette, not a bionda.
The vault was frescoed jointly in the 16th century by Giovanni Paolo di Frances del Colle and Lorenzo da Rotterdam. The left hand panel depicts the Annunciation; the right hand one has been damaged by damp.
Blessed Gioacchino Piccolomini and Blessed Francesco Patrizi and depicted in 18th century frescoes on the side walls. The former is having an ecstasy during Mass, and the latter a vision of Our Lady.
Chapel of the Seven Holy FoundersEdit
The second chapel on the left is dedicated to the Seven Holy Founders of the Servite Order. The altarpiece is by Agostino Masucci, 1727 and depicts Our Lady Granting the Habit to the Holy Founders.
The side walls have two works by Naldini, Christ Falls Under the Cross to the right, and The Burial of Christ to the left. The former has under it a memorial to Tiberio Muti, 1555 with an effigy scuplted by someone described as being of the school of Michelangelo.
Chapel of the Good ShepherdEdit
The first chapel on the left is dedicated to Christ the Good Shepherd. It is modern, having been converted from a side entrance vestibule in the 20th century and designed by Arnaldo Brandizzi in 1954. The altarpiece depicts St Anthony Mary Pucci, a Servite canonized in 1962.
The little cupola has a mosaic of The Apotheosis of St Anthony Mary Pucci by Michelangelo Bedini.
A very interesting early 17th wall memorial is here, sumptuously decorated with red and verde antico panels and with an elliptical tondo containing a portrait of a Servite friar. Oddly, the memorial has no inscription identifying him but only a tag saying mihi absit gloriari ("far be it from me to be glorified").
The palaeochristian baptistery has one of the oldest preserved baptismal fonts in Rome, and lies under the adjacent building of the Banco di Roma. This is to the left of the sanctuary.
The font was installed in a pre-existing building probably in the 5th century, although dating is difficult and the terminus ad quem for it is the 8th century. It was a plunge-pool which was circular outside and hexagonally polylobate within (this means that each corner has a little niche), measuring four metres across.
The fabric is of brick, but the lining is of marble. The depth was enough to allow immersion, as prescribed by the primitive rite of baptism (still held to by the Eastern churches).
The floor of the baptistry was raised in the early Middle Ages and a new font put on top of the old one, of identical design. It was restored in 1912 after being discovered in redevelopment.
The baptistery can be accessed via a passage from the sacristy. It used to be the case that you could ask the sacristan to unlock the door, but nowadays it is better to go to the bank. It can be seen freely from the bank's offices during business hours - they have constructed a light shaft above it, allowing a nice view.
The church is open (church website, June 2018):
Mondays to Fridays 7:00 to 24:00;
Saturdays 9:30 to 24:00;
Sundays and Solemnities 9:00 to 24:00.
The underground excavations are not open to the public.
Mass is celebrated (church website, June 2018):
Weekdays 7:45 (not July or August, Saturdays 11:00), 18:00, 22:00;
Sundays and Solemnities 9:30, 18:00, 22:00.
The friars celebrate Lauds at 7:30, Mondays to Fridays (except July and August). They must get through it in fifteen minutes.
The anniversary of the fire in 1519, and the miraculous survival of the crucifix, is still celebrated on 23 May. Other important feasts that are celebrated with great solemnity are those of Pope St Marcellus on 16 January, The Seven Holy Founders on 17 February, St Juliana Falconieri on 19 June, St Philip Benizi on 23 August, the Exaltation of the Cross on 14 September and All Saints of the Servite Order on 16 November.
This is the Lenten station churches for Wednesday after the fifth Sunday of Lent.