Königsberg fortifications

The fortifications of the former East Prussian capital Königsberg (now Kaliningrad) consist of numerous defensive walls, forts, bastions and other structures. They make up the First and the Second Defensive Belt, built in 1626—1634 and 1843—1859, respectively. The 15 metre-thick First Belt was erected due to Königsberg's vulnerability during the Polish–Swedish wars. The Second Belt was largely constructed on the place of the first one, which was in a bad condition. The new belt included twelve bastions, three ravelins, seven spoil banks and two fortresses, surrounded by water moat. Ten brick gates served as entrances and passages through defensive lines and were equipped with moveable bridges.

The Königsberg fortifications had become largely vulnerable already before the construction was finished due to rapid development of artillery. Following the military setbacks of Nazi Germany, however, they became strategically important again (particularly during the East Prussian Offensive).

The Astronomic Bastion was erected in 1855-1860 and got its name because of proximity to the Königsberg Observatory. The bastion's wall was demolished in 1910. Subsequently the bastion was used to accommodate the Russian OMON for some time. Later the structure was bought by the Russian MP Asanbuba Niudyurbegov.

The Bronsart Fort (German: Bronsart bei Mandein) was constructed in 1875-80 and is named after General Paul Bronsart von Schellendorff. It had not suffered much during military actions, remaining in quite good condition.

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