Breadcrumbs navigation

The Clementinum Astronomical Tower and Baroque Library (Astronomická věž a Barokní knihovna Klementinum)

A unique sightseeing route through a part of the Clementinum, the former Jesuit college, takes you to the Astronomical Tower and the extension that connects it to the northern wing of the Clementinum complex. Here you will have a guided tour of the Baroque Library, described as the most beautiful library in the world. You may view the Baroque Library but not enter it. The next stop on the tour is the Meridian Hall with period astronomical instruments on the 2nd floor of the Astronomical Tower. For three hundred years the giant Atlas carrying a sky full of stars on his shoulders has been looking down from the top of the tower. These have never been missing in the Clementinum - neither in star charts nor in its halls, where even W. A. Mozart himself walked and played music. The highlight of the tour is the ascent to the gallery of the longest continuously measuring meteorological station in the Czech lands.

  • Monuments & Architecture
  • house
  • tower
  • Baroque
  • views
  • Prague Visitor Pass
  • TIP

Opening hours

    • January – March
    • Whole week
    • 10.00 – 18.00
    • April – September
    • Whole week
    • 09.00 – 20.00
    • October – December
    • Whole week
    • 09.00 – 19.00

From March 27, 2024 we will be open from 9:00 to 20:00.

Entrance fee

  • basic 380 CZK
  • reduced 230 CZK
  • family 810 CZK

Practical information

Special Morning Discount:

  • 50% off the admission fee every day for the first two morning tours - 10:00 EN and 10:30 CZ

Multi-Ticket "9 buildings in 365 days"

  • adults: CZK 990
  • reduced: CZK 690

10% discount on admission when buying eTickets online

Children up to 5 years of age are admitted free of charge. Reduced admission is for children 6-15 years old, students up to 26 years old, seniors over 65 years old and people with disabilities. Persons with a ZTP/P card are admitted free of charge with 1 accompanying person. The family ticket is valid for 2 adults and up to 4 children.

Our tip: For all ticket types (except group and school tickets, lecture programs and special PCT events), you will receive a discount of CZK 50 on a 24-hour ticket for historic Tram 42 (operating Sat, Sun and public holidays 10am-6pm). The ticket can be redeemed when buying a ticket on the tram on the same day. Payment is only possible by credit card. A CZK 50 discount is also provided for each person within the family ticket. Similarly, if you already have a ticket, you can claim a 20% discount on admission to one of the towers managed by the PCT for the duration of the ticket's validity (not applicable to the Multi-Ticket).

Complete price list of admission valid from 1. 3. 2024 download HERE

Visitor rules – download HERE

SIGHTSEEING ROUTE

includes a view into the Baroque Library, the Meridian Hall and the Astronomical Tower.

  • The Baroque library hall is decorated with beautiful frescoes on the theme of science and art. In the hall there is a collection of foreign language printed theological literature and several large, historically valuable globes. The library's collection includes 27 thousand volumes, mainly from the field of theology.

  • The Meridian Hall is located on the 2nd floor of the tower. This unique room was formerly used as a giant camera obscura, where with the help of a taut string high noon was determined. In the walls of the Meridian Hall, there are 2 original astronomical instruments, namely mural quadrants used to measure the position of the stars. 

  • The 68-metre-high Astronomical Tower, which offers a magnificent view of the centre of Prague, houses an exhibition of historical measuring instruments and interesting facts about the history of the tower. Originally, since 1751 the observation tower was used for astronomical observations and it retained this function until 1938. Since 1752 it has also been associated with meteorological measurements, which became regular and systematic from 1775 onwards. For more than eighty years (1842-1928), it was also from here that the announcement of noon  was made to the inhabitants of Prague.

Tour duration approx. 50 minutes.

The Clementinum complex is managed by the National Library of the Czech Republic, while the sightseeing route is operated by Prague City Tourism.

ENTRANCES TO THE PREMISES:

  • Mariánské náměstí 5 (nearest access)
  • Karlova 1
  • Křižovnická ulice

Exclusive experiences
Would you like a private tower tour with a glass of champagne, an after-hours visit or a glimpse of places not included in the regular tour? We offer exclusive experiences at selected hotels. Ask your concierge what we can do for you.
This offer is valid for guests at the following hotels:
*****Andaz AugustineAriaCorinthiaCPI Hotels Falkensteiner Hotel MariaFour SeasonsGolden WellMandarin Oriental The EmblemThe MozartVienna House Diplomat

 

Visitors are advised of the difficulty of the Clementinum tour due to a high number of staircases and that they undertake the tour at their own risk, especially taking into account their current fitness and overall health. Lift is not available.

The sightseeing route is not wheelchair accessible.

 

The Clementinum is a national cultural monument.

Show practical information

PLEASE NOTE:

Tickets must be purchased as eTickets. Tickets can be purchased for Czech and English tours.
Tours are limited in capacity. We do not guarantee the possibility of purchasing tickets directly at the Clementinum box office.

Contacts

  • The Clementinum Astronomical Tower and Baroque Library (Astronomická věž a Barokní knihovna Klementinum)
  • Klementinum 190
  • 110 00 Praha 1 – Staré Město
  • +420221714714

You can visit

Object history

Jesuit College

The Clementinum is the second largest building complex in Prague after the Prague Castle. It was the first Jesuit college in Prague. The members of the Society of Jesus began to build it in 1556, after their arrival in Prague, where they were brought by Ferdinand I to assist him in his anti-Reformation efforts. They settled here in the Old Town, in the former Dominican monastery of St. Clement. This church later gave the name to the whole area - Clementinum.

During the period of recatholization after the defeat of the Bohemian Estates in 1620, a great building boom occurred here, which continued until the middle of the 18th century. The Jesuit College complex was built on a large plot of land where 32 houses, seven courtyards, three churches, a monastery and several gardens had previously stood. The buildings of the college were spread around five courtyards and included three churches (St. Salvator, St. Clement and the chapel of the Assumption of the Virgin Mary, known as the Vlašská Chapel), two towers, schools, a college, a library, a theatre, an observatory and its own printing house.

In the field of higher education, the Jesuit college first competed with Charles University. After 1622, however, the two colleges merged under the leadership of the Jesuits. In 1654 the Charles-Ferdinand University was founded, continuing until it was divided into Czech and German at the end of the 19th century. The Jesuits finally merged the libraries and built premises for them.

Churches

The Church of St. Salvator was once the main Jesuit church in Bohemia. It was established in 1578 on the foundations of the Gothic church of St. Clement. It was built gradually until the middle of the 17th century. The oldest part of the church is the chancel and the transept, then a triple nave with a marble portal was built, and under the leadership of Carlo Lurago, stands were built over the side aisles and stucco was applied. Later, the dome was built according to Francesco Caratti's design and finished with stucco decoration by Jan Jiří Bendel. The column in front of the entrance with stuccoes by Giovanni Battista Cometa bears statues by Jan Jiří Bendel: the church fathers, religious saints, evangelists, Jesus and the Virgin Mary. In 1714, František Maxmilián Kaňka modified the towers of the church. The church has an early Baroque confessional, decorated with statues of the twelve apostles by Jan Jiří Bendel. There is a painting by Jan Jiří Häring on the main altar.

On the corner of the chancel, the oval Vlašská Chapel of the Assumption of the Virgin Mary was built in 1590-97 by Domenico Bossi according to the design of the architect Ottorino Mascarino. The chapel served the needs of Italians settled in Prague, which is why it bears the name Vlašská (Vlaši being the old Czech word for Italians). Its broken column entrance in Karlova Street was built according to Kaňkov's design and also served as the entrance to the third church of St. Clement from 1711-15. The Baroque church was also built according to the design of Maxmilián Kaňka, simple on the outside, but expensively modified on the inside. In the niches there are statues of church fathers and evangelists by Matthias Bernard Braun. The six side altars, the pulpit, the confessional and the organ chancel are also decorated with sculptures which are mainly the work of Matyáš Braun. On one of the altars there is a painting by Petr Brandl. The church has one of the most valuable Baroque interiors in Prague.

The layout of the premises

The oldest part of the college on the side by Křižovnická Street was started by Carlo Lurago in 1653, then continued by Francesco Caratti and Giovanni Domenico Orsi (until 1679). The construction was completed in the 1830s by František Maxmilián Kaňka. In 1924-25, when the space was intended for the needs of the university library, the two-storey wing at Křižovnická Street was raised by a further, third floor. The author of the architectural design of the extension was Ladislav Machoň, working under the direction of Zdeněk Wirth. All building interventions were carried out with great sensitivity and managed to combine the precious historical environment with modern operations and equipment. Seven sculptures by Otto Gutfreund were placed on the dormers facing Platnéřská Street, symbolising the various sciences. Jaroslav Horejc (ceramics) and painter Jaroslav Benda also had a hand in the decoration.

Next to the Church of St. Salvator, the main portal leads to the first courtyard. Here stands a statue of a Prague student by Josef Max from 1847, which was erected in memory of the students who defended Prague against the Swedes in 1648. From the next courtyard is the entrance to the present library complex.

The charming, so-called vine courtyard, in the middle of which is an early Baroque stone fountain and a remnant of the first water supply system in Prague, was built by the Jesuits. In the Clementinum courtyards you can admire the largest collection of sundials in the Czech Republic.

In the eastern wing a summer refectory (today's study) was built with lavish stucco decoration and large paintings by the Jesuit Kryštof Tausch. In 1791 the first Czech industrial exhibition was held here. Behind the refectory is the famous Mirror Chapel with its rich stucco work into which mirrors are embedded. There are four paintings by Václav Vavřinec Reiner in the chapel. Today it is used for concert productions.

In the last courtyard facing Mariánské náměstí Square there is a monument to the astronomer and director of the local observatory Josef Stepling in the form of a cupid with a telescope by Ignác Platzer. It was commissioned by the Queen of Bohemia Maria Theresa. The passage in the eastern wing gives access to Mariánské náměstí Square; the passage leads to the State Technical Library. The façade of this wing has a large portal combined with a balcony and above the window there is stucco heraldic decoration by František Xaver Lederer. In the gable is a statue of St. Ignatius by Matthias Braun. The statue of St. John of Nepomuk on the façade of the entrance to the premises from Karlova Street is also from Braun’s workshop.

Astronomical Tower and meteorological measurements

The Astronomical Tower above the Clementinum’s buildings. Its builder is not certain, perhaps František Maxmilián Kaňka, Kilián Ignác Dienzenhofer or Anselmo Lurago are responsible for its construction. The tower is 68 m high, with 172 steep spiral stairs leading to the top. On the dome of the tower is a gigantic lead statue of Atlas holding a globe. The entrance to the tower is next to the entrance to the Mirror Chapel.

The history of the tower is closely related to university education, in which mathematics and astronomy played an important role. The printed and manuscript works of the university astronomers in the local library testify to the high level of science at that time. Around 1750, astronomical and climatic observations and measurements were started here and the tower was equipped with astronomical instruments. Josef Stepling, the director of the observatory, and Jan Klein, a mechanic, contributed most to the development of astronomy here. In 1775, the mathematician and physicist Antonín Strnad began systematic recording of meteorological and climatic measurements, which have been continuously taking place in the Clementinum ever since. In Berlin measurements were started earlier, but they were interrupted for many years, so the Clementinum is unique in this respect. From 1842, noon was announced from the Clementinum by the waving of a flag, which was accompanied by a cannon salute from Hradčany in the years 1891 until 1926. After 1928 the astronomical observations were moved to the new observatory in Ondřejov. The time service remained at the local tower until the Nazi occupation, and from 1926 Clementinum also provided the time signal for Czech Radio. 

Baroque Library

The Baroque library is the most beautiful of Clementinum’s halls. It was built in 1722 by Kilián Ignác Dienzenhofer and is decorated with frescoes by John Hiebel on the theme of science and art. The illusory painting of the dome symbolizes the Temple of Wisdom from Greek mythology, the sides are decorated with medallions of important Jesuits and at the front of the library is a painting of Joseph II, who enriched the Clementine library with the confiscations of the abolished monastery libraries. Around the walls there is a gallery and balcony with wrought iron railings.

Ancient globes are placed in the centre of the hall. According to legend, the Jesuits had just a single book with them when they arrived in Prague, but when the library was finished it had 20,000 volumes. After the abolition of the Jesuit college in 1773, the archbishop's seminary and part of the Prague University with the Imperial Library were located here. In 1777, the library was opened as a public and university library. The library’s collections grew rapidly. From 1782, all Prague printers handed in compulsory copies to the library, after 25 years this obligation was extended to the whole territory of Bohemia.

Today the library operates under the name of the National Library and is home to over 6 million books. The oldest book is the Vyšehrad Codex, there is Dalimil's Chronicle in a pocket edition, along with books on dogmatics, hermetics, numerology and many other rare volumes.

As part of the Prague - European City of Culture 2000 project, the Astronomical Tower and the Baroque Library Hall were renovated and opened to the public.

Other rooms

Above the Baroque Library is the Meridian Hall, where measurements and calculations were made. In addition to the astronomical instruments, there is also a string stretched taut that marks the Prague meridian, even more accurately than the line located in Old Town Square. From the Meridian Hall 65 wooden steps lead to the gallery of the tower.

Other rare spaces in the building are the Mozart Hall with its Rococo paintings, the Mathematics Hall, the Hall of Manuscripts and the Great Hall with its stucco ceiling, which now houses the card catalogue. There is also the Music Hall with a stucco figural vault with allegories of the four faculties and a rococo chapel with the altar of St. John of Nepomuk. However, these areas are not generally accessible to the public.

 

Show history

Information source: Prague City Tourism

eTickets

Choose language:
Date and time Language Available eTickets
03/20/2024 10:30 Czech less than 12 of 20
03/21/2024 10:30 Czech less than 16 of 20
03/22/2024 10:30 Czech less than 11 of 20
03/23/2024 10:30 Czech less than 1 of 20
03/23/2024 14:00 Czech less than 7 of 20
03/24/2024 10:30 Czech less than 4 of 20
03/24/2024 14:00 Czech less than 15 of 20
03/25/2024 10:30 Czech less than 20 of 20
03/26/2024 10:30 Czech less than 18 of 20
03/27/2024 11:00 Czech less than 12 of 20
03/27/2024 17:00 Czech less than 20 of 20
03/28/2024 09:30 Czech less than 14 of 20
03/28/2024 11:00 Czech less than 20 of 20
03/28/2024 17:00 Czech less than 13 of 20
03/29/2024 09:30 Czech less than 5 of 20
03/29/2024 11:00 Czech less than 20 of 20
03/29/2024 17:00 Czech less than 20 of 20
03/30/2024 09:30 Czech less than 2 of 20
03/30/2024 11:00 Czech less than 15 of 20
03/30/2024 17:00 Czech less than 20 of 20
03/31/2024 09:30 Czech less than 8 of 20
03/31/2024 11:00 Czech less than 14 of 20
03/31/2024 17:00 Czech less than 13 of 20
04/01/2024 09:30 Czech less than 17 of 20
04/01/2024 11:00 Czech less than 20 of 20
04/01/2024 14:00 Czech less than 20 of 20
04/02/2024 09:30 Czech less than 20 of 20
04/02/2024 17:00 Czech less than 20 of 20
04/03/2024 09:30 Czech less than 18 of 20
04/03/2024 17:00 Czech less than 20 of 20
04/04/2024 09:30 Czech less than 20 of 20
04/04/2024 17:00 Czech less than 20 of 20
04/05/2024 09:30 Czech less than 16 of 20
04/05/2024 17:00 Czech less than 20 of 20
04/06/2024 09:30 Czech less than 18 of 20
04/06/2024 11:00 Czech less than 20 of 20
04/06/2024 14:00 Czech less than 20 of 20
04/07/2024 09:30 Czech less than 20 of 20
04/07/2024 11:00 Czech less than 20 of 20
04/07/2024 14:00 Czech less than 20 of 20
03/20/2024 13:00 English less than 10 of 20
03/20/2024 16:00 English less than 7 of 20
03/21/2024 12:00 English less than 2 of 10
03/21/2024 13:00 English less than 20 of 20
03/21/2024 15:00 English less than 5 of 10
03/21/2024 16:00 English less than 18 of 20
03/21/2024 17:00 English less than 8 of 10
03/22/2024 12:00 English less than 5 of 10
03/22/2024 13:00 English less than 20 of 20
03/22/2024 15:00 English less than 5 of 10
03/22/2024 16:00 English less than 9 of 20
03/22/2024 17:00 English less than 1 of 10
03/23/2024 12:00 English less than 2 of 10
03/23/2024 13:00 English less than 20 of 20
03/23/2024 15:00 English less than 2 of 10
03/23/2024 16:00 English less than 10 of 20
03/23/2024 17:00 English less than 2 of 10
03/24/2024 12:00 English less than 2 of 10
03/24/2024 13:00 English less than 12 of 20
03/24/2024 15:00 English less than 3 of 10
03/24/2024 16:00 English less than 20 of 20
03/24/2024 17:00 English less than 9 of 10
03/25/2024 12:00 English less than 8 of 10
03/25/2024 13:00 English less than 20 of 20
03/25/2024 16:00 English less than 7 of 20
03/25/2024 17:00 English less than 1 of 10
03/26/2024 12:00 English less than 7 of 10
03/26/2024 13:00 English less than 14 of 20
03/26/2024 15:00 English less than 7 of 10
03/26/2024 16:00 English less than 16 of 20
03/26/2024 17:00 English less than 3 of 10
03/27/2024 12:00 English less than 2 of 10
03/27/2024 13:00 English less than 20 of 20
03/27/2024 15:00 English less than 7 of 10
03/27/2024 16:00 English less than 13 of 20
03/27/2024 18:00 English less than 8 of 10
03/27/2024 19:00 English less than 20 of 20
03/28/2024 09:00 English less than 1 of 10
03/28/2024 12:00 English less than 8 of 10
03/28/2024 13:00 English less than 12 of 20
03/28/2024 15:00 English less than 6 of 10
03/28/2024 16:00 English less than 2 of 20
03/28/2024 18:00 English less than 6 of 10
03/28/2024 19:00 English less than 20 of 20
03/29/2024 13:00 English less than 13 of 20
03/29/2024 15:00 English less than 3 of 10
03/29/2024 16:00 English less than 5 of 20
03/29/2024 19:00 English less than 20 of 20
03/30/2024 12:00 English less than 2 of 10
03/30/2024 13:00 English less than 20 of 20
03/30/2024 15:00 English less than 6 of 10
03/30/2024 16:00 English less than 18 of 20
03/30/2024 18:00 English less than 7 of 10
03/30/2024 19:00 English less than 20 of 20
03/31/2024 13:00 English less than 20 of 20
03/31/2024 15:00 English less than 2 of 10
03/31/2024 16:00 English less than 9 of 20
03/31/2024 18:00 English less than 3 of 10
03/31/2024 19:00 English less than 20 of 20
04/01/2024 09:00 English less than 10 of 10
04/01/2024 12:00 English less than 10 of 10
04/01/2024 13:00 English less than 20 of 20
04/01/2024 15:00 English less than 5 of 10
04/01/2024 16:00 English less than 20 of 20
04/01/2024 17:00 English less than 20 of 20
04/01/2024 18:00 English less than 10 of 10
04/01/2024 19:00 English less than 20 of 20
04/02/2024 09:00 English less than 4 of 10
04/02/2024 11:00 English less than 20 of 20
04/02/2024 12:00 English less than 10 of 10
04/02/2024 13:00 English less than 20 of 20
04/02/2024 15:00 English less than 10 of 10
04/02/2024 16:00 English less than 20 of 20
04/02/2024 18:00 English less than 10 of 10
04/02/2024 19:00 English less than 20 of 20
04/03/2024 09:00 English less than 10 of 10
04/03/2024 11:00 English less than 18 of 20
04/03/2024 12:00 English less than 10 of 10
04/03/2024 13:00 English less than 20 of 20
04/03/2024 15:00 English less than 10 of 10
04/03/2024 16:00 English less than 20 of 20
04/03/2024 18:00 English less than 10 of 10
04/03/2024 19:00 English less than 20 of 20
04/04/2024 09:00 English less than 10 of 10
04/04/2024 11:00 English less than 20 of 20
04/04/2024 12:00 English less than 10 of 10
04/04/2024 13:00 English less than 20 of 20
04/04/2024 15:00 English less than 10 of 10
04/04/2024 16:00 English less than 20 of 20
04/04/2024 18:00 English less than 10 of 10
04/04/2024 19:00 English less than 20 of 20
04/05/2024 09:00 English less than 10 of 10
04/05/2024 11:00 English less than 20 of 20
04/05/2024 12:00 English less than 10 of 10
04/05/2024 13:00 English less than 20 of 20
04/05/2024 15:00 English less than 7 of 10
04/05/2024 16:00 English less than 20 of 20
04/05/2024 18:00 English less than 10 of 10
04/05/2024 19:00 English less than 20 of 20
04/06/2024 09:00 English less than 10 of 10
04/06/2024 12:00 English less than 10 of 10
04/06/2024 13:00 English less than 20 of 20
04/06/2024 15:00 English less than 10 of 10
04/06/2024 16:00 English less than 18 of 20
04/06/2024 17:00 English less than 20 of 20
04/06/2024 18:00 English less than 8 of 10
04/06/2024 19:00 English less than 20 of 20
04/07/2024 09:00 English less than 10 of 10
04/07/2024 12:00 English less than 10 of 10
04/07/2024 13:00 English less than 20 of 20
04/07/2024 15:00 English less than 10 of 10
04/07/2024 16:00 English less than 20 of 20
04/07/2024 17:00 English less than 20 of 20
04/07/2024 18:00 English less than 10 of 10
04/07/2024 19:00 English less than 20 of 20