Things to Do in Ishigaki/Yaeyama in 2026 – Tours & Activities | VELTRA Discover the enchanting beauty of Hamajima, also known as the Phantom Island, a white-sand sandbar that appears only at low tide off the coast of Ishigaki Island. Accessible by kayak or boat, this surreal destination is a highlight of snorkeling and marine tours in Okinawa. Combine your visit with activities like Blue Cave snorkeling, SUP, or mangrove kayaking for a full day of adventure. Hamajima is a must-visit for those seeking stunning views and unique, Instagram-worthy experiences.