Complex sentence: The Vaca Mountains are one most of the most prominent topographic features of Solano County, forming a ridge of extremely steep slopes along the eastern border that begins at Vacaville at the south end of the range continues more than to a northern terminus at Putah Creek canyon.
Split into simpler sentences: The Vaca Mountains are one most of the most prominent topographic features of Solano County, with a ridge of extremely steep slopes along the east side. The range begins at Vacaville at the south end of the range and continues more than to a northern terminus at Putah Creek canyon.