There is such a structure on Kahoolawe and a connection to a similar navigational site on Molokai.  Why the people don't talk about it?....for its protection.  Our kupuna was much more than just keepers of our mo'olelo, they preserved our history recited in our chants.   The Kahuna knew the scientific mysteries of nature and man, some findings practiced before such people like Ericson , who wrote the book on emotional development of man.  Take time to listen to our hulu kupuna while they are still with us.