Parangdo=Ieodo (波浪島, 파랑도) or Parang Island=Ieodo Island may refer to:
Underwater reef (暗礁) located at the 4th block of seabed mining areas in the continental shelf within a part of the territory of the Republic of Korea. The top of the reef is below 4.6m sea surface thus can be seen only in severe waves. Because of this, the reef was considered to be a legendary island where sons or husbands who went out into the sea and never returned to have lived or have taken refuge. Based from the summit, the east and south form a steep slope while the west and north form a gentle slope. The total area based on depth contours of 50m is estimated to be approximately 2 ㎢(east-west 1.4 ㎞, north-south 1.8 ㎞).
It was first discovered in 1900 by a British merchant vessel the Socotra thus earning its name, Socotra Rock. The British Navy measured the reef to be 5.4m below sea level, and in 1938 Japan planned to install an artificial structure on top of the reef but it was canceled due to the Pacific War. In 1951, as a project to identify its territory, Korea explored the reef and submerged a copper plate with ‘Ieodo, territory of the Republic of Korea’ engraved on it. In 1987, the Korean Maritime and Port Administration installed a lighted buoy, the first ever structure on Ieodo.