The City wall of Visby (Swedish: Visby ringmur) is an old medieval defensive wall surrounding the city. The building of ringwall was probably started in the 13th century. Around 1280 it was rebuilt to reach its current height, along with the addition of its characteristic towers (although some towers were not constructed until the 15th century) It is part of the UNESCO World Heritage Site in Visby. The war in 1288 between the citizens of Visby and the Danish army gave the citizens of Visby a reason to continue the work with the wall. All together the city wall became 3.4 km, and it was finished in the beginning of the 14th century. At the time, the wall contained 29 towers, 27 of which are remaining today.
During the 1361 Battle of Visby, the main battle was fought within 300 meters of the North Gate of Visby (shown on the right). The peasant forces were ultimately unsuccessful, however, resulting in the citizens of Visby surrendering to the Danish forces.References:
Narikala is an ancient fortress overlooking Tbilisi, the capital of Georgia, and the Kura River. The fortress consists of two walled sections on a steep hill between the sulphur baths and the botanical gardens of Tbilisi. On the lower court there is the recently restored St Nicholas church. Newly built in 1996–1997, it replaces the original 13th-century church that was destroyed in a fire. The new church is of 'prescribed cross' type, having doors on three sides. The internal part of the church is decorated with the frescos showing scenes both from the Bible and history of Georgia.
The fortress was established in the 4th century and it was a Persian citadel. It was considerably expanded by the Umayyads in the 7th century and later, by king David the Builder (1089–1125). Most of extant fortifications date from the 16th and 17th centuries. In 1827, parts of the fortress were damaged by an earthquake and demolished.