Saumarez Reefs
Australia
Saumarez Reefs is one of the southernmost reef systems located in the Coral Sea Islands, and part of the Coral Sea Shelf; it contains three main reefs and numerous smaller reefs all of which form a large crescent-shaped formation open to the northwest, approximately 27 by 14 kilometres (17 mi × 9 mi), with an area of just under 300 km2 (120 sq mi). There are two sand cays: North East Cay and South West Cay. The reefs were first reported by Europeans on 27 February 1823 by Lieutenant John Lihou aboard the vessel Zenobia and named after Vice-Admiral of the United Kingdom James Saumarez, 1st Baron de Saumarez.
Data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).