Khan al-Umdan ('Caravanserai of the Pillars') is the largest and best preserved caravanserai (roadside inn where travelers could rest and recover from the day's journey) in Israel. Located in the Old City of Acre, it is one of the prominent projects constructed during the rule of Ahmed Jezzar Pasha in Galilee, under the Ottoman era.
Being one of four Khans in Acre, Khan al-Umdan was built in 1784 on the place of the Royal Customs house of the Kingdom of Jerusalem. It incorporates forty columns made of granite that were taken from Caesarea, Atlit and the ruins of Crusader monuments in Acre itself.
Due to its proximity to the port, Khan al-Umdan has throughout its history been an important trading spot. Merchants arriving at Acre used the khan as a warehouse while the second floor functioned as a hostel. Camel caravans once brought produce and grain from Galilean villages to the city's markets and port.
The khan later gained importance to the Baháʼí Faith (as the Khán-i-'Avámid) as it was the site where Baha'ullah used to receive guests, and later the site for a Baháʼí school.
In 1906 a clock tower was added adjacent to the main entrance to the khan to commemorate the silver jubilee of the rule of Ottoman sultan Abd al-Hamid II. It is similar to the Jaffa Clock Tower, a building dedicated to the same purpose, along with five more towers in Ottoman Palestine (in Jerusalem, Haifa, Safed, Nablus, and possibly Nazareth) and over a hundred across the entire empire.
In 2001 Khan al-Umdan, together with the rest of Acre's old city, was designated as a world heritage site. Nowadays, the khan is a major tourist attraction open all hours of the day and used as an open-air stage during festivals in the city, such as the theater festival of Acre during the month of October.
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.