Hermann Castle is a medieval castle in the city of Narva, in northeastern Estonia. The castle was established around 1256, when the area was part of the Danish Realm. The first entirely stone fortifications were built in the beginning of the 14th century, and the castle was initially a small castellum-like building with 40-meter-tall (130 ft) sides and a tower at its northwestern corner. The Livonian branch of the Teutonic Order purchased the castle in August 1346, rebuilt it into a convent, and owned it for much of its later history. The Hermann Tower was built in response to the establishment of the Ivangorod fortress by Muscovite Russia on the opposite side of the Narva river in 1492. In the 16th century, the town wall was supplemented, the gates were strengthened by adding foregates, and several wall towers were adapted to use as special cannon towers or rondels, two of which can be seen today in their reconstructed shape in the corners of the castle's western court.Photograph credit: User:A.Savin