Territory of eternal soldiers
Slunj and Rastoke geologically belong to the area of shallow karst and rest on a large tufa formation of dissolved limestone, also called “bigar” or “travertin”. River Slunjčica runs through such terrain and carries dissolved limestone rocks, increasing the tufa plateau, with medieval town of Slunj situated where the river bends. This burg on the water was built in the 13th century to fend off Tatars, and served as a fairly efficient defence from Ottoman conquerors for a long time after that. In the centre of burg, a polygonal seven-sided building, there was a castle, and possibly additional facilities. At the end of the 16th century the town is additionally fortified on the eastern side with an outer ring of fortified walls with half towers and a defensive moat.