The Homeb Silt Formation consists of eroded remnants of fine-grained alluvium that were deposited within the Kuiseb River valley in southern Namibia during the Late Pleistocene. In Holocene time the river deeply incised its valley fill leaving steep walled "Castles" of relict alluvium - the Homeb Silts. This study is based on the 25 m thick type exposure of Homeb Silts at Homeb and describes flash-flood sediments that were colonised by successive generations of opportunistic arthropods. The stacked flood units each comprise a massive tabular siltstone bed overlain by a narrower interval of rapidly alternating sandstone and siltstone with claystone veneers. These flood units are interpreted as having accumulated under semi-arid climatic conditions by episodic back-flooding of the Kuiseb River into embayments and tributary mouths.