Kianida Reef (Bulgarian: риф Кианида, romanized: rif Kianida, IPA: [ˈrif kiɐˈnidɐ]) is the 350 m long in east-west direction and 140 m wide, narrowing to the east rocky reef lying in Osogovo Bay, off the southeast extremity of Rugged Island in the South Shetland Islands. Its surface area is 4 ha.^[1] The area was visited by early 19th century sealers.^[2]

The feature is named after the phantom island of Kianida or Cianeis off the Black Sea coast of Thrace, featured on a 1467 map by Nicolaus Germanus based on Claudius Ptolemy's Geography.^[1]

Kianida Reef is located at 62°38′32″S 61°12′33″W / 62.64222°S 61.20917°W / -62.64222; -61.20917, which is 440 m southwest of Radev Point, 1.65 km west-southwest of Astor Island and 3.5 km north-northwest of Devils Point on Livingston Island. Detailed Spanish mapping in 1992, and Bulgarian mapping in 2009 and 2017.

• Península Byers, Isla Livingston. Mapa topográfico a escala 1:25000. Madrid: Servicio Geográfico del Ejército, 1992
• L. Ivanov. Antarctica: Livingston Island and Greenwich, Robert, Snow and Smith Islands. Scale 1:120000 topographic map. Troyan: Manfred Wörner Foundation, 2010. ISBN 978-954-92032-9-5 (First edition 2009. ISBN 978-954-92032-6-4)
• L. Ivanov. Antarctica: Livingston Island and Smith Island. Scale 1:100000 topographic map. Manfred Wörner Foundation, 2017. ISBN 978-619-90008-3-0
• Antarctic Digital Database (ADD). Scale 1:250000 topographic map of Antarctica. Scientific Committee on Antarctic Research (SCAR). Since 1993, regularly upgraded and updated

• List of Antarctic and subantarctic islands

• Kianida Reef. SCAR Composite Gazetteer of Antarctica
• Bulgarian Antarctic Gazetteer. Antarctic Place-names Commission. (details in Bulgarian, basic data in English)

• Kianida Reef. Adjusted Copernix satellite image

This article includes information from the Antarctic Place-names Commission of Bulgaria which is used with permission.