The main trade routes are: - to San'a, via Lahej, 227 m.; to Mocha and Hodeida, via Ta`izz, 299 m.; and to Makalla, via Nisab, 413 m.
During the World War, Turkey brought pressure to bear on certain of the tribes of the Aden Protectorate (see Arabia) and in July 1915 a Turkish army several thousand strong advanced on Lahej, the `Abdali capital (21 m.
Of Lahej), inflicted considerable loss on it, and the Turkish pressure was relieved.
The most important of these are Abu Arish, Bet el Fakih and Zubed in the western Tehama, the latter a thriving town of 20,000 inhabitants and the residence of a Turkish kaimakam; and Abyan and Lahej, the chief place of the independent Abdali tribe, in the southern Tehama.
In the following century the Turks themselves relinquished their conquests in Yemen, and the sultan of Sana established a supremacy over Aden, which was maintained until the year 1735, when the sheikh of Lahej, throwing off his allegiance, founded a line of independent sultans.