About 6,000 square kilometers

Photo from Wikimedia Commons
Black Forest (Schwarzwald)
Germany's densely wooded mountain range of fairy-tale fame/Forests
The Black Forest (Schwarzwald) in Baden-Wurttemberg, southwestern Germany, is a mountain range covered by dense dark coniferous forest. It extends about 160 km long and up to 60 km wide, covering roughly 6,000 square kilometers. The highest peak, Feldberg, reaches 1,493 m. The name comes from the canopy of evergreens blocking so much sunlight that the forest floor is perpetually dim. The Black Forest is famous for cuckoo clocks, Black Forest ham, Black Forest cake, and for inspiring the Brothers Grimm fairy tales of dark woods filled with wolves and witches.
Measurements
North to south extent
Maximum east-west extent
Above sea level
Mature Norway spruce
Mean forested altitude