In his book on the Spanish defences of Cartagena de Indias, Rodolfo Salas rightly remarks that fortifications are, fundamentally, "a matter of geography". Nowhere in the Maltese islands is "geography" so emphatically exploited for defence than along the line of natural escarpments, known as the Great Fault, found north of Mdina.

Here, in a fashion reminiscent of Roman times, the British military erected a complex network of linear fortifications in the latter half of the 19th century to provide a physical barrier to invasion. Their preoccupation, and the reason behind these fortifications, was the need to protect the naval installations in the Grand Harbour, then considered so vital for the maintenance of the British fleet, the source of Britain's imperial power in the Mediterranean Sea.

Termed, initially, as the North-West Front, the position consisted of three detached forts (Forts Bingemma, Mosta and Madalena), an intrenchment (Dwejra Lines), and a small number of batteries (Targa, San Giovanni) spaced out along the length of the escarpment. By 1897, however, the detached strongpoints were being linked together with a continuous masonry wall, 12 kilometres in length, and re-baptised the Victoria Lines, in honour of Queen Victoria's diamond jubilee.

It was the closest that military engineers in Malta ever came to building "frontier" defences. The fortified line comprised a unique ensemble of military elements built in local stone and imported materials.

The fascinating feature of the Victoria Lines, as can be seen from the photograph below, lies in the very manner in which the stone walls - the infantry parapets, stop-walls and musketry galleries - adapt themselves to the lie of the land as they follow a sinuous route along the contours of the natural escarpment.

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