Tensodo Cave (天窓洞, tensōdō) is a sea cave in Dogashima named after the skylight (tensō) that was created when a portion of the ceiling collapsed from erosion.[1]
Under the name "Dogashima Tensodo," it was designated as a Natural Monument (天然記念物, tennen kinenbutsu) on August 27, 1935.[2] Additionally, it was registered as one of the sites on the Izu Peninsula Geopark list, established in 2011.[3] Dogashima is situated roughly in the center of the western coast of the Izu Peninsula, facing Suruga Bay, and the coastal area (including Tensodo Cave) has also been designated as a Place of Scenic Beauty (名勝, meishō) under the name "Izu Southwestern Coast."[4]