Before you are the white limestone remains of an 18,000,000 year
old tropical shell reef. Formed in a shallow bay. It contains fossils
of scallops, clams, and tube worms. Mudstones of the same age, found
nearby, held fossil whales and shark teeth. Later, as the Santa Ana
Mountains rose, the rigid limestone buckled and broke along small
faults. We can now see evidence that tropical seas once covered
the spot where you stand.