The Limes Tripolitanus, the easternmost of the series of limites protecting the Latin provinces of Roman Africa, ran for some 1,000 km. from Turris Tamalleni (the modern Telmine, on the edge of the Chott el Djerid) to its eastern terminus at Arae Philaenorum (Muktar, near ‘Marble Arch’) on the border of ancient Cyrenaica. Of this total length the western 300 km. lie within the confines of the French Protectorate of Tunisia, and for this sector Cagnat's admirable summary of the archaeological evidence, although written in 1912, has not been seriously outdated by any more recent explorations. The eastern sector, also of 300 km., from the great salt-marsh of Sebcha Tauorga to Arae Philaenorum, is still completely unknown, and its character cannot be profitably discussed until exploration has been carried out : it should, however, be observed that in this eastern zone the limes must have followed the bleak shores of the Greater Syrtis, where there were few coastal centres of importance, and virtually no Romanized hinterland.