Biržai Castle was built between 1586 and 1589 by the hetman of the Grand Duchy of Lithuania, Kristupas Radvila Perkūnas and it is the best preserved bastioned castle in Lithuania.
In 1625-1627, it was occupied by the Swedish army and destroyed. A second castle took almost 50 years to restore. The first castle resembled Italian castles, while the second castle was built in Dutch style. By 1682, the fortress palace, fortifications and 21 other buildings made a huge defensive complex.
In the 17th and early 18th centuries, Biržai, situated in the north of the country, became Lithuania's main fortress in its wars with Sweden. The Polish-Lithuanian King Augustus II himself visited Biržai Castle, as well as the Russian tsars Peter I and Alexander I who came twice. In 1701, Polish-Lithuanian King Augustus II and Russian Tsar Peter I signed a treaty to unite their armies against the Swedes. However, on September 14, 1704 the fortress was destroyed for the second time by the Swedish army. It was only in 1988 that the fortress' representational palace was restored.
In 1989 Biržai Region Museum "Sėla" was opened in the castle. In 2001 the 42.5 meter fortress bridge was rebuilt based on plans by the architect Evaldas Purlys. Two years later, the roof tiles of the palace were changed. In 2008-2010, the project Strengthening Biržai Castle Walls and Foundations and Adapting the Castle for Cultural and Other Public Needs, was completed. This project was co-financed by Iceland, Lichtenstein and Norway according to the European Union (EU) funding rules. In 2010, restoration of the arsenal began sponsored by the EU structural funds and the local municipality. Restoration and research works on the fortress are ongoing.
The museum offers educational workshops, guided tours and a unique opportunity to get acquainted with beer traditions in Biržai.