If you go to Hanauma Bay, also go around the large cliff that protruds out into the sea on yout left if you are facing the ocean. You can walk around this cliff at sea level. On the other side in the cove there are some lava tubes where the waves rush up. One lg. one is called "the toilet bowl". It's been 12 yrs. since we saw it, but it seems to me it was around 6 or 7 ft. deep. Sort of just like a round toilet bowl. The seawater rises in it as the waves come itn. That's when you get in. The water level then falls and you go down with it, then up again as the water rises! You ride up & down, up & down. Really fun and different! As for the snorkeling at Hanauma Bay, it was terrific! I have heard that it now gets so crowded that sometimes they have to close it to visitors for a while if you get there too late in the day, and wait until some people leave to get in. I think it's a State Park.