The ruins located within the walls of Peel Castle are those of the former Cathedral of St German. Like the structures throughout the castle grounds, the cathedral's roof is completely missing. Robert Anderson examined the ruins to determine what repairs were required to restore the cathedral, and he reported to the island's Lieutenant Governor in 1877. However, none of the suggested repairs were carried out.
There is a pointed barrel-vaulted crypt below the chancel, measuring 10 × 5 × 3 metres, sloping to the entrance at the east. There is a cemetery in what was once the cathedral's nave.
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.