The 'Exedra' square along with its majestic Naiads fountain is one of the most modern squares in Rome .  But there is ancient history at the source of the fountain - the history of the Baths of Diocletian.  They were built in only 8 years from 298 to 306 AD and remain the largest baths in Rome and indeed the whole Roman world.

Their construction required thousands and thousands of labourers both in Rome and overseas: Greeks and Egyptians in the precious marble quarries; carpenters in the forests who provided the wood to make beams and frameworks for the vaults and arches; carriers who provided supplies and clothing; troops who refusing to obey the command to honour the traditional Gods were forced to work in the stone and sand quarries either making bricks or building the actual Baths.

The splendor of the Diocletian baths did not last for long.  In the 5th century, after the destruction of the aqueducts by the Goths, the baths fell into disuse.  For centuries they were plundered and robbed of all valuable materials until they were nothing more than a mineral quarry for mediaeval builders.  These imposing ruins help us to imagine how thousands of people were skillfully supervised in their diverse functions.   The designing, building, sculpting and painting of the baths taking place at the same time, in the same place.  Consider the definition of the building's outline, from the foundations to the roof top, the plumbing and heating systems and above all consider the fine detail in the decorative works, the dimensions of the pillars, friezes, coffers, corbels and statues each placed in their own surroundings.  Each part of this building programme was almost certainly undertaken simultaneously.  While the foundations were being laid in Rome , statues were being sculpted and trees were being felled in other areas of the Empire.

The Basilica of Santa Maria degli Angeli originated in the heart of the ancient baths in what used to be the FRIGIDARIUM (cold room).  One cannot help but marvel greatly at the magnificent ceiling in the frigidarium with its 3 great cross-vaults.  It was the brilliance of Michelangelo which transformed the frigidarium into a church nave. An undertaking entrusted to him by Pope Pius IV who wanted to fulfill the wishes of the devout Sicilian priest Antonio Lo Duca.  And, however large the space now used as a Church may be, one must remember that it only occupies the central part of the ancient baths and that in total they occupied a great surface area of 130,000 square metres .

The actual transept covers an area of 90.80 by 270 square metres.

The walls of this enormous building arise from waters heated by a sophisticated system which uses the heat from the rays of the sun and underground passages to enable the flow of water.  The passageways are made from bricks which retain heat.

The imposing presence of the baths can still be seen through the eight original rose pillars of granite.  They measure 14m in height and are more than one and a half metres in diameter.

The original Roman vault draws looks of great wonder.

The large central bath was flanked on all sides by four other baths which were probably covered over.  There was also a number of halls, the purpose of which remains a mystery.  The halls were closed off and from 1725 paintings from St Peters were placed on the newly constructed walls: 8 in the transept and 4 in the presbytery. 

The Carthusians blocked the 2 original entrances.  The entrance facing Stazione Termini was closed to enable the construction of the Chapel of Beato Albergati and the entrance facing Via XX Settembre was closed to make way for the building of the Chapel of San Bruno.

The Chapel of San Bruno now houses the great mechanical organ of Formentelli from the Millenium Jubilee.  It was a gift to Pope John Paul II from the city of Rome .  The organ has an impressive 77 ranges, 3 attachments, a total of 5400 pipes, 4 keyboards and pedals.  Its casing is made from wild cherry wood and measures 12m in height and 11m in width.  The pipes are made from 95% pure tin.  The Millenium trumpet lies horizontally at the bottom of the central arch.

To commemorate the Holy Year of 1750 the architect, Luigi Vanvitelli was entrusted with the task of creating uniformity in respect of the architecture and decorative work of the Church.  This he achieved using 8 stone pillars, identical to the originals in the transept and such composite unity can be seen in the passage from the round vestibule to the large transept and in the passage from the presbytery. Aside from this, he united the entire perimeter of the Basilica with one trabeation, identical to the trabeation and only part of which remains in the transept.  

There is a gap in the arch of the Albergati Chapel on the right side of the transept in the Basilica of Santa Maria degli Angeli. A fine ray of sunlight shines through it onto the 18th century floor of the Church. 

The ray of light moves slowly along pursuing the path of the sun. It follows the long straight line which cuts through 44m of the floor of the Basilica. After overlapping the line briefly it passes over and begins to slowly move away.  The projection of light announces the arrival of midday .  

The solar light which before the sound of the cannon of Gianicolo was used to mark the time in Rome , continues its daily ritual duty of telling the time.

The Meridian Line in Santa Maria degli Angeli is a combination of science and faith.  Pope Clemente XI Albani wanted it in order to fix the Easter feast and canon Francesco Bianchini was entrusted with the task on the occasion of the 1700 Jubilee.  The astronomer completed it in only a few years and was assisted by a mathematician Gianfranco Maraldi.  Maraldi was the nephew of Giandomenico Cassini, a scientist who created the Meridian Line in San Petronio in Bologna .  The 2 Lines are in fact very similar.

Bianchini used decorative as well as technical detail on the Sundial in Santa Maria degli Angeli.  This was intended to give it the functions of an astronomical observatory but with an artistic celebratory feel.  For each sign of the zodiac there is the corresponding constellation and in this way a celestial map is reproduced on the ground.

In 1911 the facade of the Basilica was returned to the original brick structure so that it would be more in keeping with the interior of the ancient Baths.  Today the facade holds the artistic bronze doors by Igor Mitoraj, a contemporary sculptor.  The Annunciation portrays Mary listening to an Angel on high.  The Resurrection depicts the Risen Christ and the symbol of the Cross entwined, the Cross penetrating deep into Christ's body.  The lunettes portray the Angels and the Martyrs.  These are Christian mysteries of the Redemption and are modelled on a very classic typology in keeping with the architecture and the spirituality of the building.

The circular vestibule, with Roman dome and Vanvitellian in design along with the large glass by Narciso Quagliata inside the Basilica allows one to ponder the magnificence of the building, its blend of architecture with spirituality.

The Chapels which focus on the theological themes of the crucifixion of Christ, His death and His resurrection and His appearance to Mary Magdalene are surrounded by funereal monuments made in the style of Michelangelo.  They are of important artistic and ecclesiastical figures who serve to remind us of the immortality of life, of the arts and of the act of charity.

One single large statue of San Bruno, founder of the Carthusian monks, and of the French sculptor Houdon, beside an angel shape basin of holy water from the school of Bernini, welcome pilgrims and reminds them of the presence of the Carthusian monks.  The monks inhabited both the Church and the monastery from 1581 to 1873.  While the Church still remains today the monastery is now a museum.  They also point to the Madonna of the Angels and of the Martyrs high in the apse.

Art from antiquity to the present day blend together harmoniously and without any discontinuity in Santa Maria degli Angeli. The beauty of all that is sacred creates a fascination for a culture based upon the arts, science and faith.