In and around Trondehim there are several marvelous ruins from medieval ages: King Sverre's castle Sverresborg from 1182 just outside the city centre, the cistercian monastries Tautra (built 1207) and Munkeby (built 1180), Rein monastry built by Duke Skule Bårdsson from 1226 on, and archbischop Olav Engelbrektsson's castle at Steinvikholmen (1525 - 1532). Following in the steps of the famous Norwegian painter J. C. Dahl, I have engaged myself in discussing if these ruins may be resurrected. In Kristiansand the communiy HKH Kronprindsregent Frederiks Laug af 1788 has rebuildt the cultural heritage Odderøya Castle from 1667. In Bodø has Nyholms Skandses Compagnie rebuildt the fortress Nyholmen Skandse from 1810.