Complex sentence: The landscape is characterized by a hilly transitional zone between low mountains and plain; to the west rises the Haardt at the Palatinate Forest's eastern edge, and in the east stretches the Upper Rhine Plain.
Split into simpler sentences: The landscape is characterized by a hilly transitional zone between low mountains and a plain. To the west rises the Haardt at the Palatinate Forest's eastern edge, and in the east stretches the Upper Rhine Plain.