Radzyn Chelminski was the seat of the Teutonic Knights' Commandry. The castle is one of the oldest castles built by the Teutonic Knights, built in the 13th century. In 1446 the castle went into Polish control, in 1628 during wars with the Swedes the castle was partially devastated, slowly turning into a ruin.
Currently you are still able to see the tower - damaged by artillery fire. In 1780 Prussian authorities ordered to deconstruct whatever is let of the castle. Bricks from the three wings of the castle were used to build houses for the nearby community. The castle's deconstruction was stopped towards the end of the 19th century.
References:Goryōkaku (五稜郭) (literally, 'five-point fort') is a star fort in the Japanese city of Hakodate on the island of Hokkaido. The fortress was completed in 1866. It was the main fortress of the short-lived Republic of Ezo.
Goryōkaku was designed in 1855 by Takeda Ayasaburō and Jules Brunet. Their plans was based on the work of the French architect Vauban. The fortress was completed in 1866, two years before the collapse of the Tokugawa Shogunate. It is shaped like a five-pointed star. This allowed for greater numbers of gun emplacements on its walls than a traditional Japanese fortress, and reduced the number of blind spots where a cannon could not fire.
The fort was built by the Tokugawa shogunate to protect the Tsugaru Strait against a possible invasion by the Meiji government.
Goryōkaku is famous as the site of the last battle of the Boshin War.