The only nationally designated historic site in the city, the "East Ezo Southern Domain Jinya Site Mororan Jinya Site" is one of the representative Jinya sites from the end of the early modern period in Hokkaido. In 1855, the Finance Magistrate, Nitobe Jujiro (the father of Nitobe Inazo) and 28 others conducted a preliminary survey and decided to set up the original Jinya in Hakodate, and to build a secondary Jinya in Pekereota (meaning white or bright sandy beach, near present-day Jinyacho in Muroran), which was a natural port where the Etomo basho was run.

Construction work began in March of the following year, 1856 (the 3rd year of the Ansei era) (lunar calendar), with the help of over 45 people, including 18 carpenters, four plasterers, five roofers, 40 construction workers, and woodcutters from the Nanbu domain, and the jin'ya was completed in September of the same year.

This place, where the samurai of the Nanbu clan looked out to sea and guarded the coast at the eastern end of Funka Bay at the end of the Edo period, was designated a historic site in 1934 and has been preserved ever since. Today, it is surrounded by lush greenery and is a famous cherry blossom viewing spot.