Of course, my personal theory is that it's an underwater dog house for Zeus and Apollo

If it really is a pillbox, to me it looks like it has been moved from its original location. Here's a couple in the UK that seem to be on the move. Not sure if they got they way by nature or man though ;) http://personal.tcu.edu/lsteinbach/27758c20.jpg (Photo from hidden-teesside.co.uk) http://perso...

Hi guys. I visited Magnum’s Beach (beautiful Kaiona Beach Park) last year and got to play on that concrete thing in the tidal pool just like TM. Squeee! Anyhow, I was also curious about what it is, so I emailed the archivists at the Hawai‘i State Archives and they said it is a WWII pillbox bunker. L...