Knuckle Reef () is a

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock out ...

lying off Beacon Head, Horseshoe Island, Antarctica. The reef was so named by the

UK Antarctic Place-Names Committee The UK Antarctic Place-Names Committee (or UK-APC) is a United Kingdom government committee, part of the Foreign and Commonwealth Office, responsible for recommending names of geographical locations within the British Antarctic Territory (BAT) and ...

in 1958 because the individual rocks in the reef, which are exposed at low tide, resemble the knuckles of a clenched fist.

References

Reefs of Graham Land Fallières Coast {{FallièresCoast-geo-stub