The second longest sea cave in the world is Santa Cruz Island's Painted Cave off the coast of California. Formed along a fault line, the length of the cave measures in at 1227 feet, and the entrance is 130 feet high.
The Painted Cave was named for the colorful rocks, lichen and algae featured within the cave. In the spring, a waterfall cascades down in front of the entrance.
One of the most common ways to experience this exquisite cave is to take a boat ride to the island and then explore the watery cavern via kayak.