The Temple of Neptune was erected on the Poreč forum in the 1st century. It is thought to be the biggest in Istria, although only a portion of its walls and the foundations have been preserved.
During the Antiquity, Poreč as well as all Roman towns, had a forum, the main town square known today as Marafor, and a Capitoline temple facing it. It was believed that the temple was dedicated to God Mars in light of interpreting the Marafor as the Martis forum i.e. the forum of Mars. To the north-west, also in the near vicinity of the former forum, are the remains of the Large Temple dedicated to Neptune, the god of the sea. There are some who interpret the remains as a holy ground surrounding the Capitoline from three sides. The temple, dated to the 1st century, is the biggest in Istria in spite of only a portion of its wall and foundations being preserved.
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.