Hermann Castle (also Hermannsburg, Herman Castle, Narva Castle, or Narva fortress) was founded in 1256 by the Danes and the first stone castle was built in the beginning of the 14th century. The German Livonian Teutonic knights order purchased the castle on 29 August 1346 and for most of its history the castle was German Teutonic.
Although the exact age of Narva Castle and the town cause still arguments between historians, they agree on the sequence of events. Firstly, in about the 13th century, the Danes, who had conquered Northern Estonia, built a wooden border stronghold at the crossing of the Narova River and the old road. Under the protection of the stronghold, the earlier settlement developed into the town of Narva, which obtained the Lubeck town rights in the first half of the 14th century.
Following several conflicts with the Russians, the Danes started building a stone stronghold at the beginning of the 14th century. It was a small castellum-like building with 40-metre sides and a tower, a predecessor of the today's Herman Tower, at its north-western corner. At the beginning of the 14th century, a small forecourt was established at the north side of the stronghold and, in the middle of the century, a large forecourt was added to the west side, where citizens were allowed to hide in case of wars as the town of Narva was not surrounded by a wall during the Danish rule.
In 1347 the Danish king sold Northern Estonia, including Narva, to the Livonian Order, who rebuilt the building into a convent building according to their needs. The stronghold has for the most part preserved the ground plan with its massive wings and a courtyard in the middle. The Herman Tower was also completed at the time of the Order, necessitated by the establishment of Ivangorod Castle by the Russians to the opposite side of the Narva River in 1492. The Order surrounded the town with a wall, which unfortunately has not been preserved (in 1777 there came an order to pull it down).
The Narva Castle is one of the main attractions of the city. The Narva Castle is the most diverse and best preserved defence structure in Estonia. The area of the castle is 3.2 hectares, and the highest point is the Tall Hermann Tower (51 metres). Today you can visit the museum in the castle, were the displays explain the history of Narva and the castle. There are handicraft workshops in the northern courtyard, where you can try your hand at various techniques and handicrafts.
The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.