24 hours on liner ship Ogasawara-maru from Takeshiba Pier to Chichijima island, Futami Port. And 2 hours on regular liner Hahajima-maru to Hahajima island Oki Port. 5 minutes from the port by car and 5 minutes from the parking lot on foot.
Take a short hike along the Minamizaki Nature Trail at the southern end of the island of Hahajima and you'll come to a gorgeous beach called Miyukinohama, so named because the Emperor Showa visited it in 1927 and collected samples of sea creatures here. ("Miyuki" means imperial visit.) Large rare foraminifera fossils known as nummulites can be found on the shore here.
Miyukinohama is also known as an excellent spot for snorkeling and diving. Plenty of sea creatures swim among the healthy coral. Due to the pristine surrounding, this marine park has been designated as a special protection zone and ecotourism base.