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The North Coast Ranges are mountain ranges (2,000-4,000, occasionally 6,000 feet elevation above sea level) and valleys. The ranges and valleys trend northwest, sub-parallel to the San Andreas Fault. The province terminates on the East where sedimentary strata dip beneath alluvium of the Great Central Valley; on the West by the Pacific Ocean with mountains rising sharply from uplifted and terraced, wave-cut coast; on the North by South Fork Mountain, which has the characteristic trend of the Coast Ranges, and on the South by the San Francisco Bay. The North Coast Ranges are composed of thick late Mesozoic and Cenozoic sedimentary strata. The northern Coast Ranges are dominated by irregular, knobby, landslide topography of the Franciscan Formation. The eastern border is characterized by strike-ridges and valleys in Upper Mesozoic strata. In several areas, Franciscan rocks are overlain by volcanic cones and flows of the Quien Sabe, Sonoma, and Clear Lake volcanic fields.

Extensive agricultural plains are restricted to the floodplains of the Eel and Smith rivers in the north and the interior Napa, Sonoma, Petaluma, Alexander, and Russian River valleys in the South. Principal coastal features include Humboldt Bay, Cape Mendocino, Point Arena, Tomales Bay, and Point Reyes.

A collection of unique aerial panoramas of this region may be seen in the
North Coast section of the California Atlas of Panoramic Aerial Images.