Château d'If

The Château d'If is a fortress (later a prison) located on the island of If in the Frioul Archipelago (L`Archipel du Frioul) situated in the Mediterranean Sea. The Frioul Archipelago consists of four islands, all reaching 200 hectares. The island of If, adjacent to the islands Pomeg and Raton, is the smallest island of the archipelago of Friuli (at the widest point the island reaches 180 m, and the maximum length is 300 m) and is located about a mile offshore in the Bay of Marseille in southeastern France.

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Khotyn Fortress

The Khotyn Fortress (Ukrainian: Хотинська фортеця, Polish: twierdza w Chocimiu, Turkish: Hotin Kalesi, Romanian: Cetatea Hotinului) is a fortification complex located on the right bank of the Dniester River in Khotyn town, Chernivtsi Oblast’, Ukraine.

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The beginning of Khotyn Fortress goes back to the Khotyn Fort. The fort was built in the 10^th century by Prince Vladimir Sviatoslavich as one of the border fortifications of southwestern Kyivan Rus', after he added the land of present-day Bukovina into his control. The Khotyn fort, which eventually was rebuilt into a fortress, was located on important transportation routes, which connected Scandinavia and Kyiv with the Lowlands, Podillia, Genoese and Greek colonies on the Black Sea, through Moldavia and Wallachia, on the famous "trade route from the Varangians to the Greeks". The fortification was built on a rocky cape, which was formed by the high right bank of the Dniester River and the valley of small its tributary. The cape was called "Khotin" from the Ukrainian verb "хотiти" (literally "to want") because the cape was desirable and safe place for the ancient settlers.

Bohus Fortress

Bohus Fortress (also known as Baahus or Bagahus; Norwegian: Båhus festning; Swedish: Bohus fästning) is a Swedish fortress, which is located on 40 meter cliff in Bagaholmen Island, Kungälv city, Sweden, north east from Hisingen where the Göta river splits into two branches (20 kilometres north of Gothenburg).

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Unfortunately, it is unknown, when Kungälv, or Konghelle was founded. However, Konghelle appears in the Icelandic sagas and the famous storyteller Snorri Sturluson actually visited the town himself. It is believed that Konghelle settlement existed already in the 9th century near the river with rich agriculture. In the beginning of 12th century, the Norwegian King Sigurd I Magnusson (Sigurd Jorsalfare/Sigurd the Crusader), who reigned AD 1103 – 1130, favored Konghelle and used it as the capital of Norway and an important power base.