Smoleñ Castle was built in the Gothic style in the mid-14th century probably by Otto of Pilczy to the site of earlier wooden watchtower. It was enlarged after 1350 and again in the mid-15th century. The first document dates from 1394.
The castle was destroyed by the Swedish army in 1655. It has been in ruins since them.
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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.