[masaegu]

Okinawa should be great for diving. The Ogasawara Islands would be the best as they say here in Japan. The only thing is that there are no commercial flights to Ogasawara. It takes 25 hours to go from　Tokyo to Ogasawara by boat. You could choose to dive in many other places around the country but no place beats Ogasawara or Okinawa (especially the former) in the clarity of the water.