The Danevirke is a system of Danish fortifications. This important linear defensive earthwork across the neck of the Cimbrian peninsula, was initiated by the Danes in the Nordic Iron Age at some point before 500 AD. It was later expanded multiple times during Denmark's Viking Age. The Danevirke was last used for military purposes in 1864 during the Second War of Schleswig.
The Danevirke stretches for 30 km, from the former Viking trade centre of Hedeby near Schleswig on the Baltic Sea coast in the east to the extensive marshlands in the west of the peninsula. Another wall named Østvolden, between the Schlei and Eckernförde inlets, defended the Schwansen peninsula.
According to written sources, work on the Danevirke was started by the Danish King Gudfred in 808. Fearing an invasion by the Franks, who had conquered heathen Frisia over the previous 100 years and Old Saxony in 772 to 804, Godfred began work on an enormous structure to defend his realm, separating the Jutland peninsula from the northern extent of the Frankish empire. The Danes however, were also in conflict with the Saxons south of Hedeby during the Nordic Iron Age and recent archaeological excavations have revealed that the Danevirke was initiated much earlier than King Gudfred's reign, around 500 AD and probably well before that even.
With the emergence of national states in Europe during the 1800s, the Danevirke became a powerful symbol for Denmark and for the idea of a unique Danish people and Danish culture. Throughout the nineteenth century, Denmark and Germany struggled politically and militarily for possession of the territory variously known as Sønderjylland or Slesvig by the Danes and Schleswig by the Germans. Two wars were fought, the First Schleswig War (1848-1851) and the Second Schleswig War (1864), eventually resulting in a Danish defeat and subsequent German annexation. In this hostile context, the Danevirke played an important role, at first as a mental cultural barrier against Germany, but soon also as a concrete military fortification, when it was strengthened with cannon emplacements and entrenchments in 1850 and again in 1861.
Archaeological excavations in 1969–75 established, with the help of dendrochronology, that the main structure of the Danevirke had been built in three phases between AD 737 and 968. It is, therefore, contemporary with Offa's Dyke, another great defensive structure of the late 8th century.
Recent investigations suggest that the Danevirke was not only, and not even primarily, built for military purposes. The archaeologist Henning Hellmuth Andersen found that in an early stage the main 'wall' consisted of a ditch between two low embankments. The historian argued that the Kograben south of the main wall consists of an embankment accompanied by a ditch on its northern side, which would have been counterproductive for a Danish fortification. Rather, the main construction, in its earliest stage, and the Kograben would have been shipping canals. The existence of a shortcut for shipping between the Baltic and the North Sea via the Schlei in the east and the rivers Treene and Eider in the west had long been recognized, but historians had previously believed that boats had been moved between the Schlei and Treene by portage on rollers.References:
Sirmione castle was built near the end of the 12th century as part of a defensive network surrounding Verona. The castle was maintained and extended first as part of the Veronese protection against their rivals in Milan and later under the control of the Venetian inland empire. The massive fortress is totally surrounded by water and has an inner porch which houses a Roman and Medieval lapidary. From the drawbridge, a staircase leads to the walkways above the walls, providing a marvellous view of the harbour that once sheltered the Scaliger fleet. The doors were fitted with a variety of locking systems, including a drawbridge for horses, carriages and pedestrians, a metal grate and, more recently, double hinged doors. Venice conquered Sirmione in 1405, immediately adopting provisions to render the fortress even more secure, fortifying its outer walls and widening the harbour.
Thanks to its strategical geographical location as a border outpost, Sirmione became a crucial defence and control garrison for the ruling nobles, retaining this function until the 16th century, when its role was taken up by Peschiera del Garda.