The Letterklip, Afrikaans for "lettered rock", is a provincial heritage site in Namaqualand in the Northern Cape province of South Africa. The unique rock formation was fortified by dry stone walling; it was occupied from 1901 to 1902 by British forces during the Anglo-Boer War. Various regimental badges and officers' names are engraved in the rockface.

In 1980, it was described in the Government Gazette of South Africa:

This unique rock formation was fortified and occupied from 1901 to 1902 by the British forces during the Anglo-Boer War. Various regimental badges and officers' names are engraved in the rockface.

• 
  Engravings on the rocks

• List of Castles and Fortifications in South Africa
• Military history of South Africa
• List of castles in Africa
• History of South Africa
• List of castles
• List of forts
• Second Boer War
• List of heritage sites in Northern Cape

• South African Heritage Resource Agency database