Kanmurijima (冠島) is an island in the Sea of Japan administered under Maizuru in Kyoto Prefecture.

A breeding ground for streaked shearwaters, the island was designated a Japanese natural monument (天然記念物, tennen-kinenbutsu) in 1924.

[2] Currently, the island is designated as Kanmurijima-Kutsujima wildlife protection area and any landing is prohibited.

[3] According to records of Tango no kuni fudoki, Kanmurijima and Kutsujima are the remains of a much larger island which submerged following an earthquake in 701 A.D.

The topography of the seafloor seems to support the claim, as the steep 60-metre cliff is located underwater off the eastern coast of Kanmurijima and Kutsujima, indicating a recent crustal fault.