Sineus and Truvor were the brothers of Rurik, a chieftain of the Varangian Rus tribe considered to be the founder of the Rurik dynasty, which ruled the Kievan Rus. According to the Russian Primary Chronicle, the town of Izborsk was the seat of Truvor from 862 to 864. Although his burial mound is still shown to occasional tourists, archaeological excavations of long barrows abounding in the vicinity did not reveal the presence of the Varangian settlement at the site, which indicates that Izborsk was an important centre of the early Krivichs.
Truvor's gorodishche is a settlement about half a kilometer north from the fortress that came about in the late 7th and early 8th century, and proceeded to grow twice in size in the 10th and 11th centuries. It was the predecessor of the Izborsk Fortress, protected by an oakwood wall which was later upgraded to stone, 3 meters in height by 3 meters in width in the 12th century. Though Truvor's gorodishche is mostly destroyed, a small part of the wall remains today.
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.