Sunset Boulders, also known as the Mammoth Rub, stand tall in the vista. The prehistoric nature here is like stepping back in time. Take a deep breath and feel the peace that settles over you while in their presence.
Breck Parkman, Retired Senior State Archaeologist California State Parks, discovered and presented the theory of these Rancholabrean rubbing rocks in 2001. His hypothesis is that the Columbian Mammoths rested in the cool muddy wallows to bathe nearby, then came over for a good rubbing on the rocks that formed a smooth glossy finish.
The atypically smooth, shiny patches on these blue schist rocks in Sonoma County, on the Kortum Trail, are peculiarly isolated at between 10 and 14 feet above ground, appropriate shoulder height for an adult Columbian Mammoth (Mammuthus columbi). The buffed spots on these stones are too methodical to be the result of natural forces, and they feature the same tiny gravel scratches as modern African elephant rubbing rocks.
Columbian mammoths wandered the San Francisco Bay area for many thousands of years, roaming within this neck of the woods makes sense. The Columbian mammoth descended from Eurasian mammoths that colonized 1.5-1.3 million years ago, and later hybridized with the woolly mammoth lineage.
If the rocks could speak, oh the history we could learn, and the emotion hiking in this area truly makes you feel alive.
