Map of Lord Kitchener's Blockhouse System in South Africa, 1916 (litho)

The ramifications of the blockhouse system, which played so large a part in the concluding operations in South Africa, after the second Boer War, are shown here by black circles and lines, which represent respectively the blockhouses and the barbed wire entanglements connecting them. Actually, the blockhouses were about 600 yards apart; that is, about three to every mile. It will be seen that all the railways were protected by a line of little forts along one side of the rails, and that Pretoria and Johannesburg were surrounded by a network of blockhouse cordons. The other lines sometimes followed roadways, as from Bloemfontein to Ladybrand, or they cut across the open in order to close districts used by the Boer bands, such as the Lindley-Bethlehem country. From Pretoria the blockhouses extended eastwards to Komati Poort, which is beyond the range of the map. From Field Marshal Lord Kitchener, His Life and Work for the Empire, published 1916.