3101190 Thyra Dannebod ordering the The building of the Danevirke (etching) by Frolich, Lorens (1820-1908); Private Collection; (add.info.: Thyra Dannebod ordering the The building of the Danevirke. The Danevirke was a system of fortifications built by the Danes across the Cimbrian Peninsula in Schleswig-Holstein, originally constructed as a defensive earthwork before 500 AD. Thyra was the wife of King Gorm the Old, who ruled Denmark in the mid 10th Century. Its original Illustration from Illustrated History of Denmark, by A Fabricius (Copenhagen, 1864).); 穢 Look and Learn.