The mosaics of St. Mark's Basilica have undergone many restoration
works during the centuries, since the end of the 13th century.
The tremors, the structure deformations and the atmosphere
aggressiveness are the main risk factors for the preservation of
the mosaic heritage.
Nowadays the Procuratoria of St. Mark is in charge of the mosaics
protection, maintenance and repairs and through its organs it is the
keeper of this precious masterpiece.