As a spur of rock , rock outcrop , promontory , rock castle , terrain spur or spur one of a will mountainside protruding rocks called. As Spornberg refers to all elevations which an upstream peaks form.
The property of rock spurs does not necessarily mean that they have a peak. Even a ridge that slopes sharply after only two or three sides can be called a spur, the descriptive word nose specifically describes this type of terrain. Spur mountains in the real sense, on the other hand, are characteristically separated from their main massif by a saddle . While rock spurs often stand out from the surrounding terrain not only through their shape , but often also through their geology (type of rock, tectonics), spur mountains typically mark the confluence of one or two tributaries, where they form the first higher elevation above the headland on the river. What the spur formations have in common is that they consistently represent remains of erosion , be it through more resistant rock on a steep slope , be it through old watercourses or glacier excavations, where they form, for example, an island mountain that is later further eroded or part of a Riegelberg (remainder of a valley threshold ), or were released from a valley shoulder .
Mountain spurs and spur mountains consistently form significant landmarks and are often of outstanding importance in the history of settlements.
In the past, such places on the spur, often steeply above a valley, were preferred places to build castles or fortified places, as these were particularly easy to defend because of their difficult to access location - called spur location , the shape of the castle is called sporn castle : it was often enough to fasten only the top of the slope more massive. From here, due to the exposed location, it was possible to control the traffic routes over a large area , and also to send signals to neighboring weir systems. In the event of a siege, the only problem was the supply of drinking water .
Just as often, these terrain forms are the building site for landmarks, monuments or sanctuaries of all kinds, from signaling devices that can be seen from afar to mountain churches .
Examples of such castle rocks
- In southern and central Germany mostly gentler mountain spurs:
- Hillside castle
- Promontory Fort - Bronze Age and Iron Age fortifications (cape, cliff or coastal castle)