The rugged hills and ravines of Las Trampas Regional Wilderness contain large blocks of resistant sandstone, laid down 12 or 13 million years ago, when the area was a shallow inland sea or estuary.
Photo by John Karachewskl.
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The rugged hills and ravines of Las Trampas Regional Wilderness contain large blocks of resistant sandstone, laid down 12 or 13 million years ago, when the area was a shallow inland sea or estuary.
Photo by John Karachewskl.