The Holy Spirit (Helgeand) Church, sometimes incorrectly mentioned as St. James, was built in the early 1200s. It was probably constructed as a chapel for the Danish Guild and donated by the Danish King Valdemar. In the mid-1200s the guild lost its importance and the church was sacrified as Holy Spirit Church and it also functioned as a sanctuary. The church is octagonal and built on two floors. Both floors have a common choir.
The original central tower collapsed around 1365 and Johannes van Wese donated 100 mark to the reconstruction. The church was was destroyed by fire in 1611. The church ruins are open to visitors in summer season.
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.