Santa Maria in Cosmedin

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Church of Santa Maria in Cosmedin, Rome
Santa Maria in Cosmedin
Santa Maria in Cosmedin was founded by Pope Adrian I (r. 772-95). The church, which boasts an eclectic collection of ancient Roman columns, stands on the site of an imperial-era building, perhaps the Statio Annonae. It was substantially restored in the early-12th century, when the Romanesque bell tower (ca. 1123), one of the finest in Rome, was built. It soars to a height of 34 metres (112 feet).  ​​ 

600 years later the church was given a makeover, including a new facade, by the architect Giuseppe Sardi (1680-1768). 
Old photograph of the church of Santa Maria in Cosmedin with Baroque Facade, Rome
Santa Maria in Cosmedin with an 18th Century Facade
The changes were removed at the end of the 19th century. 

The marble door case of the main door is well worth inspecting. Dating back to the 11th century, it is the work of Giovanni di Venetia. It has charming details, including little birds, foliage, a hand raised in blessing, the symbols of the Evangelists and the inscription: ME FECIT IOHANNES DE VENETIA. ​
Nave, church of Santa Maria in Cosmedin, Rome
Nave
The enclosed choir (schola cantorum) and the beautiful Cosmatesque pavement survive from the restoration work of the early-12th century, which was carried out by Cardinal Alfano.  The schola cantorum, in particular, is a precious mediaeval survival, being an enclosure for the singers of the liturgy; there is another at the church of San Clemente. The floor level is one step higher than the nave and the Cosmatesque pavement is of greater intricacy.
High altar, Santa Maria in Cosmedin, Rome.
High Altar
The late-13th century baldacchino over the high altar (an ancient Roman bath) is signed DEODATUS ME FECIT (Deodatus made me). 

In the second chapel on the left is a reliquary, which contains the purported skull of St Valentine. 

The former sacristy, now the souvenir shop, is home to a fragment of an 8th century mosaic, which was executed under Pope John VII (r. 706-707) for a chapel in the old St Peter's Basilica. It is part of an image of the Adoration of the Magi.  
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Santa Maria in Cosmedin preserves in its portico a much-photographed slab of marble, popularly known as the Mouth of Truth (Bocca della Verita). 
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