A full-scale scenic garden created as a villa for one of the city's leading wealthy merchants from around 1898 (Meiji 31). A garden pavilion in the shoin style, a mountain stream, a brick greenhouse, etc., a variety of garden spaces spread out, and in autumn, it is a place where the autumn leaves are beautiful. In 2001 (Heisei 13), it received the designation of "Place of Scenic Beauty" based on the Cultural Properties Protection Act, and became the only nationally designated cultural property garden in Hokkaido.

Miharashi Park, located on a hill near the Yunokawa Onsen town, includes the scenic garden "Kousetsuen" which the Iwafune family, who were one of the city's leading wealthy merchants, created as a villa in the 1890s during the mid-Meiji period, and on its vast grounds exceeding 40,000 tsubo (approximately 13.3 hectares), Japanese and Western style charms are scattered.

Cherry trees, including Somei Yoshino, are scattered throughout the park, and the lawn plaza, especially often used as a picnic spot, is surrounded by full-bloom flowers when spring arrives. When summer arrives, fireflies fly around the clear stream, and the sight of cicadas emerging can also be seen. In addition to this, a brick greenhouse, a shoin-style garden pavilion incorporating tea room style, etc., it has become a relaxing space with many highlights.

Also, in autumn, its appearance completely changes, and many people visit as a famous spot for autumn leaves. Centering on maple trees, garden trees number about 150 species, and if you take your time to stroll, you will unintentionally forget the time. Since 2009 (Heisei 21), the event "Hakodate MOMI-G Festa" which lights up the autumn leaves at night has been held.

In the "Green Center" which can be used as a resting place, terminals and books that allow searching for trees and wild birds in the park are installed. Free Wi-Fi is also fully equipped. There are several restrooms within the large park, but the multi-purpose toilet is inside the Green Center.