Biržai Region Museum Sėla
Juzef Naronovičius-Naronskis’ map of the Duchy of Biržai (1645) is a guide around the duchy.

Biržai Castle

In order to protect the northern borders of Lithuania and his Biržai dominion, duke Krzysztof Mikołaj Radziwiłł “The Thunderbolt” (1547-1603) built a modern fortress. The works started in 1575, when a dam was erected at the confluence of Apaščia and Agluona rivers. From 1586 to 1589, embankments were raised, palace, Evangelical Reformist church, arsenal, grain storage and warehouses, barracks and several other facilities were built. The fortress was finished in 1589. Together with the town it was a formidable deference complex. 


The Grand Duke of Lithuania and King of Poland Sigismund III Vasa and later on his descendants would not renounce their claims to the Swedish throne, which meant war for Lithuania and Poland. The war with Sweden lasted many decades (1600-1635 and 1655-1660) and in 1625 the Swedes turned Biržai Castle into ruins.


Krzysztof Radziwiłł II initiated reconstruction works on the Biržai fortress in 1637. It did not only include restoration, but also the change from Italian to Dutch style. This meant that the bastions and ramparts surrounding the fortress become its main features. Residential palace and the grounds were also reconstructed. 


In 1640, Biržai was inherited by the future Grand Hetman of Lithuania, son of Krzysztof Radziwiłł II, Janusz Radziwiłł  (1612-1655), who continued the reconstruction of the castle.


In autumn 1655, the Biržai fortress changed hands again and became Swedish.


In 1659, Janusz Radziwiłł’s cousin, Duke Bogusław Radziwiłł (1620-1669) took back the castle from the Swedes and it was once again in the possession of the Radziwiłł family. Although he resided in Königsberg (Karaliauciai), he initiated the castle's reconstruction, which has been hindered by the wars. In 1662, the technical plans of the fortress were drawn up. Unfortunately, the reconstruction came to a halt in 1669 because of the duke's death. Bogusław Radziwiłł was the last male offspring of the Biržai-Dubingiai branch of the Radziwiłł family.


In his testament, he left the fortress to his daughter Ludwika Karolina Radziwiłł (1667-1695). She restarted the reconstruction process in 1671 and work continued until 1682. This fortress was considerably larger than the first one. The palace, fortifications and 21 buildings made it a large defensive complex.


On February 26, 1701, during the Great Northern War (1700-1721), Russian Tsar Peter I and King of the Polish-Lithuanian Commonwealth Augustus II signed a treaty against the Swedes in Biržai. In August that same year, the Swedes occupied Biržai and kept hold of it until 1703.


On September 14, 1704,  the army of Swedish General Adam Ludwig Lewenhaupt took over the fortress once again. The Swedes blew up the palace and the fortress buildings before retreating. - Nemokamas lankytojų skaitliukas

Legal name: Municipality Budget Office; address: J.Radvilos 3, LT-41175, Biržai; company code: 190562082; tel. +370 450 31883; email: 

Data is accumulated and kept at the Registry of Legal Entities.