There's something romantic about sea caves. They're fun to explore, IF you know when the tide is coming in.   (Left) Corona Del Mar, California. Each time I go, this cave is different: full of sand, a few shells, or sometimes floored in bare stones. My wet footprints are a clue that I'd better not stay long.  (Right, top) San Cristóbal, Galapagos Islands. A row of small sea caves, tilted since we're bouncing over waves in an inflatable boat. See the wave crashing into the middle cave? I'd have seen the same, but closer, if I'd stayed in the Corona beach cave much longer.  (Right, lower) Also in California, a sea cave I saw while on a whale watching trip. Our 75 foot boat fit into the entrance, but it still is a fairly small sea cave.