The Lombardian city of Bergamo is composed of two parts, Città Alta (Upper Town), built up on the hills, and the Città Bassa (Lower Town), which is a lively financial, industrial and administrative centre of national importance.
A milestone in the history of Bergamo was its incorporation into the Venetian State in 1428, which lasted for over three centuries and a half. The two parts of city are separated, both physically and symbolically, by the powerful Venetian Walls, which were built by the Serenissima Republic of Venice in the second half of the 16th century to defend the city, which was the farthermost centre on the Mainland, close to the border with Milan's territory.
The walls never underwent any siege. That is why they remained almost intact to the present day. The system consist of 14 bastions, 2 platforms, 100 embrasures for cannons, 2 armouries, four gates, not to mention the underground structures featuring sallies, passages and tunnels.
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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.