Chapter 12: Outlying Oases (Ghadames and Bu-ngem)
The limitane settlements of the frontier zone lay behind a protective line of fortresses, built and manned by legionary detachments. The one of these, Ghériat el-Garbia (see Introduction to the Wadi Zem-Zem) lay on the Wadi Zemzem, on the forward edge of settled territory, covering one of the main caravan-routes from the south. The other two, Ghadames (the classical Cidamae, see 907) and Bu-Ngem, were pushed forward as outposts on the line of the other two main routes from the interior, the one following the modern western boundary of the territory, between the Sand Sea and the Hamada el-Hamra, the other being the eastern route to the Fezzan. Bu-Ngem was essentially a military station, and it may be doubted whether settled life outlasted the formal occupation of the fortress. Ghadames, on the other hand, with an adequate water-supply and sited on an important line of communication, was better favoured. Already inhabited in the first century AD (Pliny, HN V. 35, 36) it has survived to the present day as an important centre for trans-Saharan trade.
Official limitane epigraphy was illustrated [in the 1952 edition] by two texts, from the same site, cut on the same occasion: