Sanshiro Islands
Located roughly 200 meters off the Nishi-Izu coast, “Sanshiro Islands” is the collective name for the four islands of Denbei Island , Nakano Island, Okinose Island, and Taka Island. The name “Sanshiro Islands” (“Three-Four Islands”) derives from the fact that, depending on which angle you view the Islands from, there sometimes appear to be only three islands, rather than four. On days when the tidal level is less than 30 centimeters, during the period between roughly one hour before low tide and one hour after low tide, a “tombolo” causeway appears that connects the Sehama Coast to Denbei Island; this tombolo has been designated a Prefectural Natural Monument. The tombolo can be seen during the daytime between February and mid-October (the exact times vary from day to day).