Amasya Castle (Turkish: Amasya Kalesi), aka Harşene Castle, is a fortress located in Amasya, northern Turkey. The castle is located north of Amasya and the river Yeşilırmak on the steep rocks called Mount Harşene. It was attacked, ruined, changed hand and restored many times in the history during the Persian, Roman, Pontic and Byzantine era. The castle was severely ruined during the battles between the Romans and Pontics. It was substantially restored after the conquest of Amasya by the Ottomans in 1075, and remained in use until the 18th century when it lost its military importance.