The famous Kvitsøy Stone Cross was erected between 800–1050 AD. Some say it was put there by English missionaries in the 900s while others claim it was raised by Erling Skjalgsson and Olav Haraldsson, Viking chiefs, in 1016. There are a number of large stone crosses along the west coast of the Norway. Kvitsøy is first mentioned in the Snorre Saga, where Snorre records a truce being made between King Olaf II of Norway later to be known as St. Olav (Hellige Olav) and Erling Sjalgsson, under the stone cross.
References:The Château du Haut-Koenigsbourg is situated in a strategic area on a rocky spur overlooking the Upper Rhine Plain, it was used by successive powers from the Middle Ages until the Thirty Years' War when it was abandoned. From 1900 to 1908 it was rebuilt at the behest of the German kaiser Wilhelm II. Today it is a major tourist site, attracting more than 500,000 visitors a year.
The first records of a castle built by the Hohenstaufens date back to 1147. The fortress changed its name to Koenigsburg (royal castle) around 1157. The castle was handed over to the Tiersteins by the Habsburgs following its destruction in 1462. They rebuilt and enlarged it, installing a defensive system designed to withstand artillery fire.
The fortification work accomplished over the 15th century did not suffice to keep the Swedish artillery at bay during the Thirty Years War, and the defences were overrun.