Steinerne Brücke in Regensburg is a 12th-century bridge across the Danube linking the Old Town with Stadtamhof. For more than 800 years, until the 1930s, it was the city's only bridge across the river. It is a masterwork of medieval construction and an emblem of the city.
Charlemagne had a wooden bridge built at Regensburg, approximately 100 metres east of the present bridge, but it was inadequate for the traffic and vulnerable to floods, so it was decided to replace it with a stone bridge. The Stone Bridge was built in only eleven years, probably in 1135–46. Louis VII of France and his army used it to cross the Danube on their way to the Second Crusade. It served as a model for other stone bridges built in Europe in the 12th and 13th centuries. For centuries it was the only bridge over the river between Ulm and Vienna, making Regensburg into a major centre of trade and government.
The Stone Bridge is an arch bridge with 16 arches. At the south end, the first arch and first pier were incorporated into the Regensburg Salt Store when it was built in 1616–20, but remain in place under the approach road to the bridge. An archaeological investigation was performed in 2009, and revealed fire damage during the Middle Ages.
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.