五稜郭是日本最後的內戰「箱館戰爭」的舞台，現已開放成為著名的公園，全年有許多遊客造訪。園內的博物館展示著當時的豐富史料，及戰爭時使用的大炮等遺跡。每年春天，1,660株多的櫻花同時盛開，是北海道內屈指可數的櫻花名勝。園區周邊設有美術館，可以欣賞跟函館有相關的美術作品；從「五稜郭鐵塔」可以瞭望五稜郭公園；以及介紹函館和北海道漁業歷史的文化資料館等。
Goryōkaku is a star fort in the Japanese city of Hakodate on the island of Hokkaido. It was the main fortress of the short-lived Republic of Ezo. Goryōkaku was designed in 1855 by Takeda Hisaburō. His plan was based on the work of the French architect Vauban. 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.
