So na Caçana dates from the Talayotic period (1000-700 B.C.) and remained occupied until the arrival of the Romans. It contains up to ten large structures. At first it was thought to be a settlement but archaeological excavation work uncovered up to three taula enclosures, which suggested it was more likely to have been a sanctuary and ceremonial site that may have been used by more than one community.The main features of the site are the central monument, the entrance to which was closed off in the 1st century B.C., and the taula enclosure on the west side. The capital of the taula has not survived, but you can see an unusual pilaster at the back. Also of interest are the niches in the perimeter wall. Archaeological excavation work inside the enclosure has uncovered evidence of the rituals carried out in this type of enclosure. There is also a necropolis in the area, comprising two natural caves and three underground burial chambers.
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.