Complex sentence: The highest peak is the Monte Corrasi (1,463 m), while the average altitude is about 900 m. The Supramonte is characterized by Karstic highlands in which the rivers created deep ravines and canyons.
Split into simpler sentences: The highest peak is the Monte Corrasi (1,463 m). The inner area of the massif has an average altitude of 900 m, including Karstic highlands in which the rivers created deep ravines and canyons.