With its rather angular - in places trapezoidally-shaped - summits, the Northern Black Forest rises above the Rhine Plain by more than . By contrast, its eastern slopes descend gradually and there is less of a height difference with its neighbouring regions. Its highest peak is the Hornisgrinde at sea level (NHN). Woods cover on average 73% of the whole land area and make the Northern Black Forest the most cohesive forested part of the Black Forest, but there are also extensive areas of so-called Grinden: treeless, wet heaths, on its highland slopes.