Ayasofya:

Hagia Sophia (meaning: Holy Wisdom), officially known as the Ayasofya-i Kebîr Mosque, is an important historical structure in Istanbul that was converted from a church to a mosque. It was a basilica-plan patriarchal cathedral built by Byzantine Emperor Justinianus I between 532-537 in the old city center of Istanbul's historical peninsula. After the conquest of Istanbul by the Ottomans in 1453, it was converted into a mosque by Mehmed II. It was taken under renovation by a decree issued by Mustafa Kemal Atatürk in 1934, and in 1935, with the decision of the Council of Ministers, it was converted into a museum, excavation and renovation work was started and it served as a museum from 1935 to 2020. It was converted back into a mosque in 2020. The upper floor of the mosque began to serve as a paid museum in 2024. Thus, the lower floor of Hagia Sophia became a mosque and the upper floor became a museum.

Tonsberg Fortress Castle:

Dating in 871, Tønsberg is commonly believed to have been the oldest Norwegian town and one of the oldest recorded fortified locations in Norway. According to Snorri Sturluson, Tønsberg was founded before the Battle of Hafrsfjord under which King Harald I of Norway united Norway under his rule. Tønsberg was an important trading center and site of the Haugating, the Thing (assembly) for Vestfold and one of Norway's most important places for the proclamation of kings. In the 13th century, King Haakon Haakonson built a castle, Tunsberghus, at the location of the modern Tønsberg municipality. It was located at what was formerly one of the most important harbors in Norway. The castle was greatly expanded during the reigns of Håkon Håkonsson and Magnus Lagabøte, who added large walls, towers, residential halls and a church. The last king of a fully independent Norway, Håkon V Magnusson, died at the castle in 1319. 

Hansestadt Stralsund:

Stralsund was granted Lübeck city rights in 1234. This makes it the oldest city in Pomerania. As a founding member of the Hanseatic League, the city achieved considerable prosperity through international trade. The old town with its numerous architectural monuments and particularly valuable examples of brick Gothic architecture has been a UNESCO World Heritage Site since 2002 with the title Old Towns of Stralsund and Wismar. Stralsund is a recreational resort and important tourist center in the southern Baltic region, and is also known for the maritime museum with the Ozeaneum Stralsund, the Stralsund Museum and for events such as the annual Wallenstein Days and the Rügen Bridge Marathon. Tourism dominates the economy. Other economic sectors include public administration, shipbuilding and mechanical engineering, service companies, logistics, the health industry and companies in the field of information technology and biomedical technology. The medium-sized town has been the seat of Stralsund University since 1991, and neighboring Parow has been home to the German Naval Technology School since 1996.