Goryokaku Park
Goryokaku, a Western-style fortress, was built in 1866 and served as the political capital of Hokkaido until the new Meiji government took over. It later became a popular tourist attraction after it was opened to the public as "Goryokaku Park" in 1914 and was designated as a national special historic site.
I went in winter, and the scenery was beautiful. You can see the star-shaped park! When it snows, everything turns pure white, and the views are amazing.