Safed Koh (" white mountain"), in many respects the most remarkable range of mountains on the north-west frontier of Pakistan, extending like a 14,000 ft. wall, straight and rigid, towering above all surrounding hills, from the mass of mountains which overlook Kabul on the south-east to the frontiers of India, and preserving a strike which - being more or less perpendicular to the border line - is in strange contrast to the usual conformation of frontier ridge and valley. The highest. peak, Sikaram, is 15,620 ft. above sea-level, and yet it is not a conspicuous point on this unusually straight-backed range. Geographically the Safed Koh is not an isolated range, for there is no break in the continuity of water divide which connects it with the great Shandur offshoot of the Hindu Kush except the narrow trough of the Kabul river, which cuts a deep waterway across where it makes its way from Dakka into the Peshawar plains. Strategically it is an important topographical feature, for it divides the basin of the Kabul river and the Khyber route from the valley of Kurram, leaving no practicable pass across its rugged crest to connect the two. Its western slopes, where it abuts on the mountain masses which dominate the Kabul plain, are forest-covered and picturesque, with deep glens intersecting them, and bold craggy ridges; the same may be said of the northern spurs which reach downward through the Shinwari country towards Gandamak and Jalalabad. Here the snow lies late and moisture is abundant - but on the southern sun-scorched cliffs but little vegetation is to be seen. Approaching the Peshawar plains the Safed Koh throws off long spurs eastward, and amongst the foothills of these eastern spurs the Afridi Tirah long remained hidden from European eyes.