Daugavgriva Fortress is located in Riga at the mouth of the Western Dvina (Daugava). The history of the fortress goes back more than 4 centuries. During the Swedish-Polish war (early 17th century), the Swedes built the first fortifications here. Built in 1608, the fortification resembled a star in its configuration. Throughout the 17th century. Swedes strengthened and rebuilt the defences.
In 1710, the fortification consisted of six fortifications with water moats, stone escarpments and covered passages. The fortress contained barracks and powder cellars. After the end of the Northern War (1700-1721) the fortress was repeatedly expanded and rebuilt. Near Daugavgrīva fortress a settlement was established. At that time the fortress was used as a prison in the Russian Empire. Thus, for example, the deposed emperor Ivan the 4th and his parents were imprisoned here.
During the reign of Empress Catherine II, a powerful fortress was built, adapted to the military technology of the time. At that time Daugavgrīva Fortress Daugavgrīva fortress was one of the strongest Russian fortresses. Since 1860 the fortress was called Dunamünde, and in 1893 it was renamed to Ust-Dvinsk. In the middle of the 19th century, a telegraph line was brought to the fortress, which was the first not only in Russia, but also in all of north-eastern Europe.
A large winter port was built between the fortress and the sea; at one time, dozens and even hundreds of sailing ships “wintered” there. Towards the end of the 18th century, a breakwater was built. In 1863, a cast-iron lighthouse was erected, the height of which was just over 30 metres high. During the World War I, the lighthouse was blown up, a new one was built in 1921, its height was 33.5 metres. In 1873, a railway line was laid to the fortress was reached by a railway connecting Riga railway station and the winter port.
In 1904 the fortress was rebuilt again, in the period from 1914 to 1916 the fortress was significantly strengthened. Between 1914 and 1916, the fortress was considerably strengthened, mainly the fortifications, directed to the sea. At the beginning of September 1917, the Russian troops left the fortress, which changed hands thereafter. During the period of Latvian independence, an army camp was located in the Daugavgriva fortress; during Soviet times there was a secret military facility here. In post-Soviet times, despite the fact that the fortress belonged to the Latvian Army, it was used by commercial firms.
