Kojosan Hill, 175.2 meters high, looks out over the Sea of Suo, the Sea of Hibiki, Mt. Sarakura, etc. at a distance, and overlooks the Kanmon Port. On this hill was Moji Castle, which is believed to have been constructed by order of Taira no Tomomori to prepare for a battle with the Minamoto clan.

The hilltop currently serves as the site of the well-maintained Mekari Park, and the stone monument to the former site of Moji Castle and the small remains of stone walls alone show us what the castle looked like at that time.

With a maintained promenade, the hill is an ideal place to stroll around, and provides a beautiful view of the rising sun, sunset, and illuminated streets at night, whenever you come here. A gun battery storage space and a powder magazine used during WWII still remain around the hilltop.