The dolos, a wave-dissipating concrete block, was invented in South Africa in 1963 and named after the Afrikaans word for “knucklebones” due to its crisscross shape. This design helps interlock each dolos structure over time, reducing wave energy and coastal erosion. Ngqura Port has the most dolosse in the country, with 20,800 blocks (30 tonnes each) spanning 2.7 km.

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