The site of Bangor Cathedral was originally occupied by St Deiniol's Monastery, established in the sixth century around 530 on land given by the king of Gwynedd, Maelgwn Gwynedd. Deiniol is said to have been consecrated as a bishop by Saint David, making him the first Bishop of Bangor. This monastery was sacked in 634 and again in 1073. Nothing of the original building survives.
The Synod of Westminster in 1102 is recorded as taking measures to restore Bangor Cathedral, but the earliest part of the present building was built during the episcopate of Bishop David (1120–1139) with the assistance of the king of Gwynedd, Gruffudd ap Cynan, who donated money towards the project and was buried by the high altar on his death in 1137. This was a cruciform building in the Norman style, about 44 yards in length. Gruffudd's son, Owain Gwynedd, was also buried here, as was his brother Cadwaladr. Giraldus Cambrensis describes a service held here in 1188 when the Archbishop of Canterbury celebrated Mass.
In 1211, the cathedral was destroyed by King John's army, on a raid into Gwynedd.
In the 13th century the original apse was removed and the choir was extended to its present length. The church was badly damaged when King Edward I invaded Gwynedd in 1282. There was extensive rebuilding in this period, under the first Bishop Anian, with the transepts and crossing rebuilt. The nave was rebuilt in the late 14th century.
The cathedral was said to have been burnt to the ground in 1402 during the rebellion of Owain Glyndŵr, but there is no contemporary evidence for this, though it may well have been damaged. There certainly was extensive reconstruction from the end of the 15th century, completed in 1532. There is a Latin inscription over the tower doorway recording that Bishop Skevington built the tower in 1532, though it was not complete when Skevington died in 1533. Some work was done during the 18th century and in 1824-1825.
The building as seen today is the result of extensive work carried out under the supervision of George Gilbert Scott, starting in 1868. Scott's design originally called for a high central tower and spire, but this was never completed as cracks appeared which were thought to indicate subsidence of the foundations. The tower was therefore left as a low structure.
The cathedral contains the 'Mostyn Christ', a figure of the Pensive Christ carved in oak and thought to date from the late 15th century, depicting Christ prior to the crucifixion, seated on a rock and wearing the crown of thorns.
The cathedral also contains a number of pieces of woodwork created by Robert Thompson, including 5 of his famous wooden mice.
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.