Kokemäki Castle (Kokemäen linna) was a medieval castle in Kokemäki town. The time of its foundation is unclear, but the castle was most likely completed in 1324-1325. It was demolished in 1367 by order of King Albert, as the local residents complained of heavy taxation for the upkeep of the castle. The castle was located on the Linnaluoto Island in the river Kokemäenjoki.
Kokemäki Castle was the administrative centre of Kokemäenkartano slottslän. Its function was similar to that of the castles of Turku, Häme and Vyborg, which are still preserved today. The only known reference to Kokemäki Castle is King Albert's warrant for the demolition and relocation of the castle, dated 12 July 1367. It was probably built of limestone and equipped with a round tower. In 1364–1365 Kokemäki Castle was besieged by the army of King Albert as the castle was under the rule of Magnus IV of Sweden.
Archaeological excavations were made in 1885. Various items were found which were dated to the late Bronze Age, as well as to the 13th and 14th century. After the demolition of Kokemäki Castle a new castle, Aborch, was established. Location of this castle is uncertain, since it was disbanded in the 1410s. It was probably built 1.5 kilometres upstream at the same location as the later Kokemäenkartano manor.References:
The Petersberg Citadel is one of the largest extant early-modern citadels in Europe and covers the whole north-western part of the Erfurt city centre. It was built after 1665 on Petersberg hill and was in military use until 1963. It dates from a time when Erfurt was ruled by the Electors of Mainz and is a unique example of the European style of fortress construction. Beneath the citadel is an underground maze of passageways that can be visited on guided tours organised by Erfurt Tourist Office.
The citadel was originally built on the site of a medieval Benedictine Monastery and the earliest parts of the complex date from the 12th century. Erfurt has also been ruled by Sweden, Prussia, Napoleon, the German Empire, the Nazis, and post-World War II Soviet occupying forces, and it was part of the German Democratic Republic (East Germany). All of these regimes used Petersberg Citadel and had an influence on its development. The baroque fortress was in military use until 1963. Since German reunification in 1990, the citadel has undergone significant restoration and it is now open to the public as a historic site.