This church belongs to the most important and the most beautiful examples of the Prague Baroque. It is remarkable especially for its monumental construction and husky dome. Together with Lesser Tower Bridge Towers it represents an inseparable part of Prague scenery.
It was built on the site of the former parish church from the end of the 13th century. Its construction was started in 1673 and it was not completed until 1756, just shortly before the abolition of the Jesuit Order (1773). It has always formed a part of the adjacent Jesuits college. The most outstanding Baroque architects participated in the completion and the artistic decoration of the church. Among these artists we have to mention Krystof and Kilian Ignac Dienzenhofers, Jan Hennevogel, Ignac Platzer, Jan Lukas Kraker and last but not least Karel Skreta. The Lesser Town Square served as a marketplace as early as in the Romanesque period.
The baroque construction of St. Nicholas Cathedral was was carried out in the first half of the 18th century under the supervision of the renown architects Christoph and Kilian Ignaz Dientzenhofers. Within the Lesser Town, this church is considered to be one of the most beautiful and stylistically pure examples of high-baroque architecture situated north of the Alps. In its interior you might also admire the beautiful organ dating back to the mid-18th century. Even Wolgang Amadeus Mozart played this organ during his stays in Prague. It is quite interesting that the belfry has never formed a part of the church. It has always been the property of the municipality of Malá Strana. Consequently, it bears its own house number (556) and has its own entrance. The belfry which was used as the Prague watchtower, was built after the completion of the church by Kilian Ignaz Dientzenhofer and itself completed in 1755 by his pupil and son-in-law Anselmo Luragho.
The last watchman used to live here until 1891. Until that time, he was obliged to ring a bell in the event of fire and to hang a red flag from the window in the direction of the conflagration during the day as well as a lantern during the night. Actually, the bells were hung in the tower five years before its completion. The tower and the dome of the church intentionally both have the same height of 74 m.
The observatory of national security
It is possible to visit the former observatory of national security in the belfry of the St. Nicholas Church in the Lesser Town. The observatory was situated here from 1952 till the Velvet revolution in 1989. The national security, or StB, was a secret police organisation during the era of communism in Czechoslovakia, famous for monitoring people. One of the activities in this place was monitoring the events of the American and German embassies. In this place, which is 70 meters above the ground level, you can find a permanent exhibition devoted to the administration of monitoring various people by the StB. All the documents and photos come from archives of security branch. The place has been maintained to look as it did during the communist era. The members of the StB kept at their disposal a divan bed, a table with a writing desk and a chair. They also had a wireless station which was used for the communication with their colleagues from counter-intelligence. Members of counter-intelligence then documented all observations. From beer bottle labels on the walls inside, we can easily imagine how the StB operatives passed their time. This observatory represents unique proof of how authorities acted during the communist era, and forms an important part of the Czechoslovakian history, which should be never forgetten.