The coastline at Garrapata State Park in California is full of tide pools, chasms, and sea caves. You don't really notice the sea caves unless you climb down onto and around the rocky shoreline. This cave was a pleasant surprise and the overcast day actually helped even out the photo. Had there been a blue sky I never would have been able to get all of the detail inside of the cave without blowing out the sky.
Shot on my Canon T3i with Tamron 10-24mm Lens. 1/250 seconds; f/8; ISO 100