相模川
The Tanzawa Mountain Range, part of the Kantō Mountain Range, contains Mount Hiru (), the highest peak in the prefecture. Other mountains measure similar mid-range heights: Mount Hinokiboramaru (), Mount Tanzawa, (), Mount Ōmuro (), Mount Himetsugi (), and Mount Usu (). The mountain range is lower in height southward leading to Hadano Basin to the Ōiso Hills. At the eastern foothills of the mountain range lies the Isehara Plateau and across the Sagami River the Sagamino plateau.