Sea Lion Caves

Sea Lion Caves are a connected system of sea caves and caverns open to the Pacific Ocean in the U.S. state of Oregon. They are located 11 miles north of Florence on U.S. Highway 101, about midpoint on the 400 miles Oregon Coast. In this area Highway 101 follows a steep and undeveloped seascape 300 feet above sea level. Human access to the caves is through a gift shop building.
The cave system is at sea level and the ocean continually washes into the main cavern which has a floor area of about 2 acres and a vaulted rock dome about 125 feet high. Southward from the main chamber, a low passage runs 1,000 feet to a sea level opening. This corridor is flooded at high tide and free of water at low tide. The western entrance is a short, high passage through which the ocean washes at all tide levels. At the north, a third entrance is about 50 feet above the ocean which serves as an elevated observation area where the entire underground cave system and its wildlife are visible.

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