While the bishopric has been established since at least the 4th century, the present Acqui Cathedral building was begun under bishop Primo (989-1018) and was consecrated in 1067 by bishop Guido. The ground plan is in the shape of a Latin cross, and there are five aisles (but until the 18th century, only three), terminating in three semi-circular apses. Of the Romanesque structure there still remain visible the apses, the transept, and the crypt, which underlies both the transept and the choir. The remainder has been subject to further work in later centuries.
The terracotta bell tower was finished in 1479, and the bells moved from the old campanile. The main entrance in marble, by Giovanni Antonio Pilacorte, dates from 1481, and the rose window above it from around the same date, while the portico is 17th century. The interior was re-fitted in Baroque woodwork, and was decorated with frescos and stucco work from the 17th to the 19th centuries.
Next door are the canons' cloisters of the late 15th century, and some Roman ruins.
The 19th century pulpit and the Baroque altar of Saint Guido in the transept are worthy of note. The most important work of art in the cathedral by far however is the triptych of the Madonna di Montserrat, the Annunciation to the Virgin of Montserrat, the work of the 15th century Spanish painter Bartolomé Bermejo, in the chapter house.
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.