Inside One of the World's Largest Sea Caves, 90 Miles West of L.A.
One of the perks of visiting two of the outer islands in Channel Islands National Park is a trip to Painted Cave along the northwest coastline of Santa Cruz Island. The park's main transit vendor, Island Packers, makes a point of doing frequent stops during travels because the park is not just land based, but also miles of protected water in the Channel Islands National Marine Sanctuary. Whales, dolphins and other sea life are often spotted, but one of the most popular attractions from a boaters perspective is Painted Cave.
It's size--100-foot wide and one quarter-mile long--makes it one of the largest and deepest sea caves in the world (and one survey considers it the biggest of all). It's name doesn't come from Chumash Indian paintings like the state park in Santa Barbara County, but rather from colorful rocks, flowers and algaes. In the Spring, you can sometimes experience a waterfall over the entrance.
Bigger boats (as seen in the video below) can fit into the cave's first chamber while kayakers can explore deeper inside where flashlights are used.
To see Painted Cave, there are a few options. Pending weather and water, Island Packers will visit on trips departing Santa Rosa and San Miguel islands. Another park vendor, Truth Aquatics, offers trips as well. Additionally, hooking up with the various park kayak vendors can get you an adventurous and up-close look at the cave (and many other sea caves). A full list of options are here, but you should know that you are allowed to go on your own, provided you can get yourself there (just be safe and make sure you know the rules).
A video of going into Painted Cave is below.