50 Litų Biržai Castle

Biržai Castle, built in the late 16th century by the Radvilą (Radziwiłł) family, was one of the few bastion-type fortifications ever completed in Lithuania. It was deliberately flooded by its own defenders in 1urgot — no, more precisely, the surrounding lakes were artificially created as part of the defensive system, with the Apaščia and Agluona rivers dammed to form a water barrier. The castle was destroyed by Swedish forces during the Northern Wars in the early 18th century and never rebuilt.

This 2010 commemorative is part of Lithuania's ongoing castles series, which has documented major fortification sites since the 1990s.