The Golden Gate of Vladimir, constructed between 1158 and 1164, is the only preserved ancient Russian city gate. A museum inside focuses on the history of the Mongol invasion of Russia in the 13th century.
The Golden Gates existed in the holiest cities of Eastern Orthodoxy: Jerusalem, Constantinople, and Kiev. On making Vladimir his capital, Andrew the Pious aspired to emulate these structures, commissioning a lofty tower over the city's main gate to be erected in limestone and lined with golden plaques. According to ancient Russian chronicles, the masons were invited from Friedrich Barbarossa. The main arch used to stand 15 meters tall. The structure was topped with a barbican church dedicated to the Deposition of the Virgin's Robe and symbolizing the Theotokos's protection of Andrew's capital.
The gate survived the Mongol destruction of Vladimir in 1237. By the late 18th century, however, the structure had so deteriorated that Catherine the Great was afraid to pass through the arch for fear of its tumbling down. In 1779, she ordered detailed measurements and drawings of the monument to be executed. In 1795, after many discussions, the vaults and barbican church were demolished. Two flanking round towers were constructed in order to reinforce the structure, and artisans then reconstructed the barbican, following the drawings made in 1779.
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.