The Clementinum in Prague: Baroque Library and Visitor Guide
Baroque library, astronomical tower, tickets and updated opening hours
Ion López Bidaguren
Art historian and licensed tour guide with over 17 years in tourism. Former educator at the Guggenheim Bilbao, guiding in Prague for 10+ years in Spanish, English and Italian.
March 10, 2026 · 8 min readIf you have seen on Instagram a photo of a hall with golden bookshelves reaching the ceiling, antique terrestrial globes and a baroque fresco covering the entire vault, it was probably the Baroque Library of the Clementinum in Prague.
But most travellers arrive without a clear idea of what the Clementinum actually is, whether you can enter the library, how much it costs, or how the visit works. Many confuse it with the Tower of Books, which is something completely different.
I have been running tours in Prague for more than 10 years and I walk past the Clementinum several times a day. It is on Karlova street, right on the route between the Old Town Square and the Charles Bridge, you literally walk past it without knowing what you are missing. In this article I tell you what it is, how to visit it and whether it is worth the price.
What is the Clementinum?
The Clementinum (Klementinum in Czech) is the second largest building complex in Prague after the Castle. It covers more than 20,000 m², an entire city block, and from the outside it looks like just another Old Town building. But inside it is a different story.
It was founded by the Jesuits in 1556 as a college. Over more than 200 years they expanded it into a massive complex that included churches, libraries, observatories and study halls. When the Jesuit order was dissolved in 1773, the building passed into state hands.
Today it is the headquarters of the National Library of the Czech Republic , an active institution with millions of volumes. But what you come to see as a traveller is concentrated in four spaces:
The Baroque Library (Baroque Hall), the famous hall. Golden bookshelves, historic terrestrial globes, ceiling frescoes representing the Temple of Wisdom. It was completed in 1727 and contains more than 27,000 volumes of theological literature.
The Astronomical Tower, 68 metres tall, 172 steps up to the viewing balcony at 52 metres. Panoramic views of the Old Town. At the top, a statue of Atlas holding a celestial sphere.
The Meridian Hall, on the second floor of the tower. Here solar noon was measured for centuries using a string that crosses the hall as the "Prague meridian". It contains period astronomical instruments.
The Mirror Chapel (Zrcadlová kaple), a baroque chapel from 1724-1725, with marble walls, ceilings decorated with mirrors and two organs. Today it functions as a classical music concert hall.
The baroque library: what you need to know
The ceiling frescoes were painted by Josef Hiebel, allegories of science and art under the title "Temple of Wisdom". The terrestrial globes in the centre of the hall are originals from the 18th century.
But there are three things you need to know before going:
You cannot enter the hall. The Baroque Library is observed from the doorway. You look inside, but you do not walk among the bookshelves. It is an active hall of the National Library.
It can only be visited with a guided tour. You cannot enter the Clementinum independently. The only way to access it is by purchasing the guided tour of approximately 50 minutes.
Photography is strictly prohibited inside the Baroque Library. The images you see on Instagram are promotional or taken with special permits.
Note: do not confuse it with the Tower of Books
This is important because it happens constantly. Many travellers confuse the Clementinum with the Tower of Books ("Idiom") (→ ES-40), the contemporary art installation by Matej Krén consisting of 8,000 stacked books with mirrors that create an infinite tunnel effect.
They are completely different things:
- Idiom is in the Municipal Library of Prague (a different building). It is free, self-guided and takes 10-20 minutes.
- The Clementinum is the National Library. It is paid, visited with a guide and lasts about 50 minutes.
The detail that creates the confusion: both buildings are in the same square (Mariánské náměstí), less than 1 minute walking from each other. But they are different institutions with different experiences. If you want to see both, perfect, but organise them separately.
The astronomical tower of the Clementinum
The astronomical tower is the second part of the guided tour, and for me, the one that surprises people the most.
You climb 172 steps up a narrow staircase to the circular balcony at 52 metres high. The views are panoramic: the red rooftops of the Old Town, the church towers, the Charles Bridge (→ ES-15) in the background, and on clear days you can make out Prague Castle on the other side of the river.
But the most striking fact is not the views, it is the history. From this tower, daily meteorological observations have been recorded since 1775. Without interruption. It is one of the longest continuous meteorological records in the world, more than 250 years of data on temperature, pressure and precipitation at the same exact point.
The tower is included in the same ticket as the Baroque Library. You do not need to buy a separate entry.
Practical note: the stairs are narrow and steep. It is not accessible for people with reduced mobility nor advisable with pushchairs. If you suffer from vertigo or knee problems, bear that in mind before climbing.
Tickets and opening hours for the Clementinum
The guided tour of the Klementinum includes three stops: Baroque Library, Meridian Hall and Astronomical Tower. Tours depart every 20-30 minutes in Czech and English.
Prices 2026
| Category | Price (CZK) | Price (~EUR) |
|---|---|---|
| Adult | 380 | ~16€ |
| Young person (16-26 years) | 300 | ~12€ |
| Child (6-15) / Senior (65+) | 230 | ~10€ |
| Children under 5 | Free | – |
| Family | 50 CZK discount per person | – |
Early bird discount: the first two tours of the day (09:00 in English, 09:30 in Czech) have a 50% discount. Only approximately 20 tickets available, exclusively online. They sell out quickly.
Opening hours
| Period | Hours |
|---|---|
| January - March | 10:00-18:00 |
| April - September | 09:00-20:00 |
| October - December | 09:00-19:00 |
Tour duration: approximately 50 minutes.
How to buy
Tickets are purchased as eTickets. Every Monday new tickets are released for the following 2 weeks. Capacity is limited; in high season (June to September) they sell out quickly.
Recommendation: buy online several days in advance. If you go in summer and turn up without a reservation, you may not get a ticket that day.
Holders of a Clementinum ticket receive a 20% discount on other towers managed by Prague City Tourism.
How to get to the Clementinum
Address: Klementinum 190, Staré Město (Old Town), Prague 1.
It is on Karlova street (Karlova ulice), which is the pedestrian road connecting the Old Town Square with the Charles Bridge. If you walk from one to the other, you pass in front of the Clementinum without realising it; it is one of those enormous buildings that blend in with the rest of the street.
| From | Walking time |
|---|---|
| Tram Karlovy lázně | ~1 minute |
| Old Town Square | ~3 minutes |
| Charles Bridge | ~2 minutes |
| Metro Staroměstská (Line A) | ~2 minutes |
There is no car access; the entire area is pedestrianised. The nearest tram stop is Karlovy lázně, and the closest metro station is Staroměstská on Line A (green).
Concerts in the Mirror Chapel
The Mirror Chapel hosts classical music concerts regularly. The Royal Czech Orchestra performs here with repertoire by Mozart, Dvořák and Smetana, with musicians from the Czech Philharmonic. Tickets from 700 CZK (~28€).
The concerts are independent of the guided tour to the Baroque Library; they are purchased separately and accessed through a different entrance. You can do both on the same day, but you need two separate tickets.
Visit with ODISEA Tours
The Clementinum is right on the route of our free tour of the Old Town. Karlova street is part of the itinerary, so we walk past the complex. The guide points out the building, explains its Jesuit history and clears up the confusion with the Tower of Books.
To visit the interior, the Baroque Library and Astronomical Tower, you need the separate guided tour (we do not go inside during the free tour).
My recommendation: do the free tour of Prague in Spanish first. The guide gives you the historical context of the Old Town, the Jesuits, the Baroque, the transition to the Czech state. Afterwards, the visit to the interior makes much more sense. Without context, the Baroque Library is beautiful but you do not understand what you are looking at.
Schedule: every day at 10:00 and 14:00. Meeting point: in front of ZARA, Na Příkopě 15/583. Duration: approximately 2h30. Tip-based model.
Frequently asked questions
Can you visit the Clementinum library independently? No. Only with a guided tour (approximately 50 minutes). You observe the Baroque Library from the doorway; you cannot walk through the hall. The tour also includes the Astronomical Tower and the Meridian Hall.
How much does entry to the Clementinum in Prague cost? Adult: 380 CZK (~16€). Young people 16-26: 300 CZK. Children 6-15 / seniors 65+: 230 CZK. Under 5s: free. The first two tours of the day have a 50% discount (approximately 20 places, online only).
How long does the Clementinum visit last? Approximately 50 minutes. It includes the Baroque Library, the Meridian Hall and the climb up the Astronomical Tower (172 steps).
Can you take photos in the Clementinum library? No. Photography is strictly prohibited inside the Baroque Library. The photos you see on social media are promotional or taken with special permits. Rules may vary in the tower and the Meridian Hall; ask the guide.
Is the Clementinum worth visiting? Yes. The Baroque Library is one of the most photographed in Europe: frescoes, golden bookshelves and 18th-century terrestrial globes. The Astronomical Tower offers views that few travellers know about (most people climb the Prague Astronomical Clock (→ ES-14) but do not know this tower exists). 380 CZK for 50 minutes with access to three spaces is a reasonable price.
What is the difference between the Clementinum and the Tower of Books? Completely different attractions. The Clementinum is an 18th-century baroque complex with a historic library, astronomical tower and chapel; paid guided tour (380 CZK). The Tower of Books ("Idiom") (→ ES-40) is a contemporary art installation of 8,000 books with mirrors in the Municipal Library (different building, free entry). Both in the same square, less than 1 minute apart, which feeds the confusion.
The Clementinum is 3 minutes from the Old Town Square and the Astronomical Clock (→ ES-14), and 2 minutes from the Charles Bridge (→ ES-15). The Tower of Books (→ ES-40) is literally next door, in the same square. Combine all three in one morning if your route includes the Old Town; the ODISEA free tour (→ ES-01) passes right in front of the Clementinum.