The three caves in this area were formed when sea levels were much higher and sand and surf carved them out.
Waikapala'e is one of two wet caves here and is accessible via a short, uphill trail that leads from a parking lot near the first wet cave, Waikanaloa. If you are in the mood for an icy dip, this cave offers an unusual experience. At the back of the main cave there is an opening to a smaller cave called The Blue Room. You can only get there by swimming. When you look back to where the sun is shining in the cave the whole room turns blue.
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Both wet caves are fed from underground springs which dump into the ocean. The level of water in the caves is affected by the tide. The blue effect is most striking when the water level is higher.
One word of caution, as with any freshwater on the island there is a possible threat of leptospirosis, a deadly bacteria - don't go swimming if you have any open wounds and do not drink the water.
From Ha'ena, take Highway 560 west. Both wet caves are located on the left just before Mile Marker #10, past the Ha'ena Beach Park. A short trail uphill leads to this cave.